The violence occurred despite the presence of nearly 600 city and state officers to help with a crowd that was nearly double the size that attended last year, according to Police Commissioner Frederick H. Bealefeld III.
"Our citizens, our visitors deserve better, and [they] will get better," Mayor Stephanie Rawlings-Blake said Tuesday. Of the injured child, she said: "It's a worst nightmare for any parent to have this happen on a day that we expect to celebrate ... that we expect to have good memories.
"We will find out who did this," the mayor said.
Baltimore police said they were confident that they would be able to track down the man who fatally stabbed 26-year-old Joseph Lorenzo Calo, based on a photo provided by a witness who was in the area.
Calo, of Opelika, Ala., was in town visiting family and got into a shoving match with a group of men outside McCormick & Schmick's Seafood Restaurant on Pier 6, according to Bealefeld. Later, the commissioner said, Calo "re-engaged" the suspect and was stabbed in the neck with a broken bottle.
The shooting of the 4-year-old remained a mystery for investigators, however. The boy, identified by WBAL-TV as Kavin Benson of Middle River, was walking with his father and the father's pregnant fiancee on Pratt Street near a police command center for tactical officers when the boy's father heard a pop and saw that the boy was bleeding from the leg.
Doctors at Johns Hopkins Children's Center determined that the boy had a small-caliber bullet lodged near his knee. But Bealefeld said none of the officers at the heavily saturated scene heard a gunshot, and camera footage doesn't show signs of a gun being fired nearby. No shell casings were recovered.
Officials are exploring whether the bullet, which Bealefeld said entered the boy's leg with a "downward trajectory," may have been fired into the air and struck the boy as it came back down. "It is possible that the bullet came from elsewhere," said Anthony Guglielmi, the Police Department's chief spokesman. "That makes our job a lot more difficult."
The violence shook residents and visitors who attended the event, and was the topic of much discussion on social media sites and talk radio. Just hours earlier, Bealefeld had given assurances that visitors would be safe, saying a shooting in a downtown parking garage at 2 a.m. was not random, but was two former neighbors settling an old score.
Jean Holzhueter, who lives within walking distance of the Inner Harbor, has attended the New Year's and Independence Day fireworks for many years, but she said that Monday was the first time she felt unsafe during the festivities.
Holzhueter said she was standing near the water's edge by the Baltimore Area Visitors Center when a fight broke out and people gathered around to watch and record the fracas on cellphones and cameras. Television news cameras captured the fight and aired it on the 11 p.m. broadcasts. A second fight started nearby at the end of the fireworks, she said.
"It was kind of like a moving mob," Holzhueter said. Although police responded quickly, she said, Holzhueter was afraid she would be pushed into the water by the expanding crowd. "It was just scary how fast it grew."
Nicola Henry, a 21-year-old from Jamaica, is a first-time Baltimore visitor. "I'm disappointed," she said. "Baltimore is a nice place. I guess things like that happen, but it puts a damper on how I view the city."
Mark and Peg Wytrwal of Las Vegas, dressed in matching patriotic T-shirts, said they came to Baltimore to enjoy the history. "It's sad to say, but that's the world we live in today," Mark Wytrwal said of the violence. "We won't let it deter us from enjoying the city, though."
Kirby Fowler, president of the Downtown Partnership, said the publicity was the "kind you don't want to have," but said downtown remains a safe and growing area.
"Some people already have a view of Baltimore as an unsafe place. This type of incident will fuel that perception," Fowler said. "However, there are many people who understand that the real Baltimore is a growing and diverse place and recognize that these events sometimes happen."
Added Bill Gilmore of the Baltimore Office of Promotion and the Arts: "You need to march along. You can't let an incident like this deter your Independence Day celebrations. You can't let the actions of a few people affect the good work and entertainment of the public at large."
With the same number of people — 104 — killed in the city as this time last year, and shootings up 6 percent, violence has not been a prominent issue in the mayor's race. Mayoral candidates condemned the crimes but had offered few concrete policy proposals.
Rawlings-Blake said the fight that ended with the fatal stabbing was "clearly preventable," noting that while police had a heavy presence, those involved should have walked away or been separated. "Somebody has to have cooler heads," she said.
Last year, Baltimore police stepped up enforcement during July Fourth fireworks after a late-June shooting in the Inner Harbor. About a week before the 2010 fireworks, one member of a group of teens opened fire on another gathering of youths on a walkway near the World Trade Center, sending one man to the hospital.
Earlier this year, a teen was stabbed at Gay and Fayette streets the day after Easter when at least 100 teenagers roamed the streets near the Inner Harbor for more than two hours as police used megaphones to order them to leave.
Violence at the harbor received more attention during the spring and summer of 2009, with a string of random assaults by juveniles, a double stabbing in April and a double shooting in August. Much of the attention focused on nightclubs downtown and in Mount Vernon.
Celebratory gunfire during holidays has also been a concern, and if the bullet that struck the 4-year-old had been fired in the air, it would not be without precedent. In 2001, a 19-year-old girl was hospitalized after a stray bullet lodged in her forehead from gunfire during Inner Harbor fireworks after New Year's Eve. In 1992 during Fourth of July celebrations, a 50-year-old man was fatally shot while he watched the fireworks from a rooftop on East Baltimore Street.
Baltimore was also not alone in violence at Independence Day celebrations. According to news reports, a man was stabbed Monday night in Philadelphia near City Hall, and three people were shot downtown in Indianapolis.
Bealefeld said police commanders would be assessing how the massive deployment of officers was used. Officers now have BlackBerry smartphones equipped with GPS that allows commanders to track their movements throughout the city. Bealefeld said there were officers on the pier where the stabbing occurred, but he would not say how many or whether they responded to the first fight appropriately.
Officials also declined to comment on the possibility that the city might consider security checkpoints used in other places. Bealefeld said officials would be conducting a "top-to-bottom" review.
Jurg W. Mattman, a California-based security and crowd control expert, said that for a city of Baltimore's size and financial means, the installation of security checkpoints would most likely be unreasonable. The added cost of checkpoints, he said, might lead the city to cancel the fireworks display.
In Washington, the U.S. Park Police can afford to fence off access to the National Mall and institute a limited number of entry checkpoints where people may be searched because costs are supported by federal funds and policing duties are divided among several agencies.
Even in a post-Sept. 11 world, people in Baltimore are not as acclimated as those in Washington to heavy public security and might reject the idea of being screened before watching an Independence Day show, Mattman said.
One small security precaution Baltimore could take, Mattman said, is posting signs near the viewing areas to remind people that firearms and other weapons are prohibited. It's a minor step that deters people from bringing banned items into sporting events and concerts, he said.
"There's no 100 percent security," Mattman said. "You do the best you can. If that's not enough, then you cancel the event."
Overall, Baltimore police said they arrested 30 people and cited 20 juveniles for curfew violations and weapons Monday night.
"Getting kids out of downtown was cumbersome for us," Guglielmi said. Police did not chase groups that ran through the harbor, because they were posing no threat to themselves or others. However, when curfew went into effect at 11 p.m., officers — including the commissioner and his deputy commissioner — made arrests after giving warnings, Guglielmi said.
Though police said they had little information about how the 4-year-old might have been struck by a bullet, others said they had seen a disturbance and heard what sounded like shots in that area.
Resident Ali Cannavino was driving back from Baltimore-Washington International Thurgood Marshall Airport with her boyfriend about 10:30 p.m. when she said they got stuck in downtown traffic. While stopped next to the Metro station on East Baltimore Street between Charles and St. Paul streets, they saw "what looked like a scuffle," Cannavino, 27, said. "Then we heard a shot."
At first they thought the sound was fireworks, but then "we heard another one, and everyone started screaming and running."
Another resident, 31-year-old Jason Castonguay, said he saw the same incident. While he believed the noise to be fireworks, his brother-in-law thought it was gunshots and they saw people scattering. Bealefeld said there were "lots of fireworks going off" at that time and said there's no ballistic evidence to suggest a shooting occurred there.
Jacinta Ocampo, 45, was working in the McCormick & Schmick's Seafood Restaurant parking lot at the time of the stabbing and described the scene as chaotic. "The only thing I saw was the blood afterwards," she said. "I was really, really upset."
On Tuesday afternoon, a dozen white roses, wrapped in green tissue paper, had been placed on the brick walkway in front of the restaurant entrance.
Sun reporters Liz F. Kay, Steve Kilar, Julie Scharper, Julie Baughman and Rebekah Brown contributed to this article.