"I was afraid of what I was going to see," Spilker said. "I looked up and there was a big cloud of black smoke."

As several helicopters circled in the sky Tuesday afternoon, onlookers gathered near the corner of 66th Street and Pulaski Highway, many capturing photos of black smoke rising into the air with their camera phones.

At Northeastern Supply, another warehouse a few blocks from the derailment, Lori Everson was sitting in her office and heard the explosion, which knocked items from the shelves. She said she thought a vehicle from Pulaski Highway had driven into her building.

About 50 employees at the warehouse ran outside and watched a huge plume of black smoke fill the sky, Everson said.

"That was an amazing explosion," she said. "I don't think I've ever heard anything that loud before."

Everson and her co-workers went back inside to watch the coverage of the derailment on television. They had scratchy throats and burning eyes from the smoke, she said.

In the small community north of Philadelphia Road near the crash site, residents were still in wonder at the scale of the blast, but were not worried about leaving a few hours later.

The communities off Longview Avenue, Wilhelm Avenue and Summit Avenue were within the 20-block optional evacuation radius, but the westerly wind carrying smoke toward Baltimore City put some residents at ease.

Fred Snyder, 49, said he would continue to monitor the wind direction. As long as the smoke stayed away, he felt comfortable staying home.

"They say this is going to last all night," Snyder said. "If it starts shifting, then maybe I'll think twice."

Anna Valentine, 83, was in her kitchen, sitting next to her husband, when she heard "boom!" and had to calm herself so she wouldn't have a heart attack, she said. She wears a hearing aid and worried her eardrums would blow out.

In the early evening, residents of Maryland Manor gathered in their yards as smoke still rose above their neighborhood. Boys skateboarded in the street, and emergency vehicles made their way through the local roads.

"I'm really concerned about the fumes," said resident Delores O'Neil, a county school bus driver.

O'Neil said she wanted to stay in her home rather than evacuate. She came home to shattered glass in her den, where frames holding pictures of her son's wedding and her grandchildren had been knocked off the walls in the blast.

"It kind of makes me sad," she said, looking at a small pile of glass on the floor. "It could have been worse."

Vincent Chiu, manager of Ha Ha Food Market near Pulaski Highway and 66th Street, just a few blocks from the crash site, said glass doors were blown off their tracks, boxes of food fell from shelves and the kitchen ceiling fell in.

"The whole ceiling here, there were people working in here when the whole ceiling fell," Chiu said. "They were making dim sum."

Baltimore Sun reporters Carrie Wells and Jennifer Marshall contributed to this article.