Police have urged the public to avoid the area.
On Tuesday, an explosion in Youngstown, Ohio, injured seven people, including one seriously, and left two people missing, authorities said.
The explosion occurred near Central Square on Tuesday afternoon, prompting residents to avoid the area.
Officials said it was unclear what caused the explosion at the building, which houses a Chase bank and apartments.
Youngstown Fire Chief Barry Finlay initially classified the incident as a natural gas explosion, but later said crews were working to determine if there was a gas leak.
“I know for sure, there was an explosion,” Finley told reporters during a press conference Tuesday evening.
Mercy Health said Tuesday evening that it was treating seven people injured in the incident, with one in critical condition.
Following a search of the building, a man and a woman were unaccounted for, Finley said. A fire department official said the man was a bank employee. Police are searching for his vehicle after the blast, he said.
“Until then, we have to assume he’s in the building,” Finley said.
The ground floor collapsed and it flooded, and search crews are working to send a mini-drone up there to help with the search effort, Finley said.
Chase Bank is located on the ground floor of the building, with 12 floors of apartments above.
Officials said streets in the neighborhood were closed to traffic indefinitely as the building was removed and threatened with collapse.
A Chase spokesperson told ABC News, “The company is in close contact with local authorities to verify the safety of the building and everyone in the area.”
“We will then work to determine what happened and assess the damage,” the spokesman said.
Officials said there is no suspicious activity at this time.