The seemingly random shootings picked up steam, with four over 48 hours this week after one last week. Once ballistics tests indicated a single gunman might be responsible, area law enforcement agencies were put on alert.
Within hours, Anne Arundel County police officers spotted and pulled over the 1999 Lincoln Town Car that had been identified through previous surveillance footage.
Police say the driver, 35-year-old Hong Young, was carrying the .380-caliber pistol they believe was used in the shootings. Young, a former corrections officer from Beltsville, was taken into custody, and police say they plan to charge him with attempted first-degree murder and other counts.
"Officers shared information and ultimately located and removed this person from the community before he took someone's life," Anne Arundel County Police Chief Tim Altomare said Wednesday.
Authorities believe Young is responsible for five shootings that occurred across the region since last Tuesday. Two people suffered non-life-threatening injuries from one of the incidents.
Officials acknowledged that as the shootings mounted, they feared a repeat of the 2002 Beltway sniper spree that gripped that region and left 10 people dead.
Young was being held under police watch at a local hospital where he was receiving treatment. Authorities did not say what kind of treatment he was receiving, nor did they know a motive for the shooting spree.
Young, who has no criminal history, worked as a state corrections officer at a medium security facility in Jessup for two years until resigning last May. Court records also show he was in the process of a divorce.
Police said his weapon was legally acquired.
The string of shootings began last week, when a vehicle driven by a 61-year-old man was shot at Feb. 24 as he drove through Arundel Mills. That was followed Monday by a report of shots fired at a Wa-Mart in Laurel, and another near the AMC Theatres at The Mall in Columbia.
At that point, police in Anne Arundel and Howard counties began comparing notes.
"The coordination efforts started as we knew something was going on that was a little unusual," said Lt. T.J. Smith, an Anne Arundel police spokesman.
On Tuesday, the case took on greater urgency when two men traveling in a dump truck were fired at from an Intercounty Connector overpass, bullets shooting out their back windows and injuring both of them. That was followed later in the day by shots fired at a building affiliated with the National Security Agency at Fort Meade.
The situation "rapidly evolved from a single incident," Altomare said. "We kicked every effort into overdrive" as soon as "maybes" became links.
But though police had surveillance images from some of the crime scenes, showing a blue or gray Lincoln Town Car, they did not have a sharp image of the suspect, and could not discern a license plate number.
With motorists being urged to stay off the roads Tuesday due to icy conditions, Arundel and Howard police pushed extra officers into patrol to scour the streets for the vehicle.
Around 10:30 p.m. Tuesday, near the Costco at Arundel Mills, where the first shooting was reported last week, county patrol officers Matthew Hall and Mason Ellis spotted Young's town car and pulled him over.
"He was hiding in plain sight," in the same car, Smith said.
Though investigators said they did not know of a motive, they do not believe there were any links to terrorism.
"Buildings were fired upon, so that takes you a little bit into the mindset of this individual that buildings were shot at," Smith told reporters at a news conference Wednesday.
Though the FBI was coordinating the investigation late Tuesday after shots were fired on the federal installation, U.S. Attorney Rod Rosenstein said federal and state authorities decided that Young's cases should be handled in state court.
Court records show that Young filed for divorce from his wife on Sept. 24. The filing, however, was dismissed Monday by the court due to inaction by both parties. In his petition for absolute divorce, Young said the couple had been married since 2007 and did not state any grounds for the divorce.
His wife, Bunnary Ngo, said in a phone interview Wednesday with The Baltimore Sun that she has been living in California for several months.
"I am going to divorce him," she said.
Ngo said she had received a call several days ago from Young's mother, who was concerned because she had not seen him and he was not returning calls.
"Everybody was trying to reach him," Ngo said.
Ngo said she has not talked with her husband recently and couldn't remember the last time they spoke. She said she was unaware of the shootings and expressed concern for his safety.
Other family members could not be reached.
Young worked for the Department of Public Safety and Correctional Services from January 2012 until May 2014, according to officials and records. He earned $41,830 in fiscal year 2013, and Secretary Stephen T. Moyer said Wednesday that there was "nothing significant" in his personnel file.
Records show Young lives at a home in the 4900 block of Daisey Creek Terrace in Beltsville. The home, valued at $460,000, is not owned by Young, but by someone who is identified as the sole proprietor of a janitorial services company.
Joy and Saramma Abraham have lived next door to the home for more than 10 years, but said they knew little about the family who lived there. They estimated that four to five people lived in the home and thought they were from Cambodia.
"Several times we tried talking to him, but he never looks at your face." Abraham said about Young. "He mostly just stares at the ground."
Saramma Abraham said she thought it was "scary" that Hong had been arrested in connection with the shootings but said there were no indications of any violence or trouble next door.
On Wednesday, forensic investigators were seen going in and out of the home. Later in the day, Prince George's County police posted photos of 10 weapons and hundreds of rounds of ammunition that were recovered there.
The two men who were injured in the Tuesday shooting on the ICC worked for Nelson Tree Specialist, a tree removal and trimming company with offices in Highland and a shop in Beltsville, according to office manager Gary Cooper.
Cooper said Wednesday morning that the two men were back at home and "doing OK," though they remained shaken from the incident.
Altomare, the Arundel police chief, praised his officers, including Hall, Ellis, and Detective Jeff Golas.
"It's going to be a case study in good police work, done by good street cops, done by a fantastic detective who's home getting some sleep," he said.
Baltimore Sun Media Group reporters Ben Weathers, Kevin Rector, Justin George and Ian Duncan contributed to this article.