Bridgeport police arrested a person of interest Thursday after an explosion rocked an apartment building and forced the evacuation of the area early that morning. Nelson Diaz, of Bridgeport, is charged with disorderly conduct and is being held on a $25,000 bond while local, state and federal law enforcement continue their investigation.

It happened at 1512 North Ave. just before 12:30 a.m. in the hallway outside of an apartment on the third floor. The explosion appears to have blown the door frame apart. Incredibly, no one was hurt.

“We heard a big boom, shook the whole building! Went upstairs to check what was going on. Apparently, somebody blew somebody’s door off,” said Paquito Deleon, who lives in the building. “We were terrified.”

Police and firefighters initially responded to a 911 call reporting smoke coming from the building’s third floor but once on scene, realized some sort of explosive device had gone off. They called in the State Police Bomb Squad and the FBI, who evacuated the building, along with surrounding homes, as a precaution. Police said over 100 people were initially affected, but many were allowed back after a sweep of the building came up empty.

Those who live at 1512 North Ave. spent the night across the street at Geraldine Johnson Elementary School, which the city closed Thursday so it could be a temporary shelter for those tenants. They were let back into the building around 9:45 a.m.

“There was a slight delay due to an issue with the fire alarm system. It appeared to have been damaged in the explosion, so I had to have that checked out before I could allow the tenants back into the apartment building,” explained Dep. Fire Marshal Robert Marrero.

Sophia Dossantos, 10, was among the group who spent the early morning hours at the school.

“It was really fun there. I met two new friends,” Sophia told News 12.

She’d been asleep at home when her mom woke her up and explained they needed to leave. Sophia described the scene in the hall as her family left their apartment.

“I saw like all smoke. I was like, ‘What’s going on? Is there a fire or something?’ And then I saw wooden stuff falling down, and I was like, ‘Oh, my God, what happened?’” she recalled.

Investigators are still working to answer that question. Diaz was seen roaming the halls right before the explosion and quickly leaving the building just seconds after it, according to police. They also said he was seen roaming the hallways the night before.

At a news conference Thursday afternoon, Chief Roderick Porter said he didn’t believe Diaz was a tenant of the building. Porter also said police haven’t established a relationship between him and the people living in the apartment that took the brunt of the blast.

“We hope to know soon what the device was and the intent behind the incident,” Porter stated.

Reinaldo Fernandes, an employee of the company that manages the property, told News 12 the explosion occurred outside of an apartment where a 14-year-old girl was inside at the time. Fernandes said she was home alone because the teen’s mother was working.

“Thank God she was in the bathroom and was not in the kitchen because if she was in the kitchen, she could get hurt,” Fernandes said.

Fernandes was on site Thursday helping with repairs.

“The damage to the door—it’s totally like in parts, even the trims around it. There 2X4 that goes behind the door. It's all damaged. And a 2X4—you don't break a 2X4 so easy,” Fernandes stated. “Even like in the kitchen, you can see the refrigerator has some marks of the damage.”

Fernandes told News 12 the damage extended down the whole hallway, causing cracks in the ceiling, evidence that whatever caused the explosion was strong.

“Everybody here knows everybody. We're a close neighborhood. And it really shook us,” Deleon said. “I was just glad that everybody was safe and mighty God took care of us.”

“We want to reassure the community that there's no ongoing threat to the community,” Porter stated.