DENVER (CBS4) – One person is in custody after a fire and a series of explosions ripped through two apartments in southeast Denver and injured two people.

Denver police said they are investigating the incident as a possible a hash oil explosion. It happened at approximately 8 a.m. inside the Parliament Apartments on the 4300 block of South Quebec Street, close to the Denver Tech Center.

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(credit: CBS)

(credit: CBS)

“It sounded like booms were going off, almost like aerosol tanks were maybe blowing up,” said a witness. “It was like ‘Boom, boom.'”

A firefighter sustained minor injuries battling the fire. Someone else was also injured and had to be taken to the hospital. That person was later taken into custody and their name hasn’t been released.

It took about 30 minutes for firefighters to get the fire under control, but by then it had already caused heavy damage to the two units.

“It was almost like gunshots. It literally sounded like gunshots. So people are backing up — everybody’s watching the fire — but people are backing up because it just keeps exploding and exploding,” said witness Kimberly Moran Blad.

Multiple neighbors say they saw two people running out of one of the apartments screaming for help.

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“Somebody asked for help, I called 911, and at that point the flames just started going off,” said Sophie Noorts, another witness.

The witness says he still can’t believe that a possible hash oil explosion could put so many residents at risk.

“A really nice couple was living next to them up there,” the witness said. “They don’t think about who it’s affecting. It’s just unfortunate.”

Police told CBS4 they are looking into the possibility of a possible second suspect in the case.

(credit: CBS)

(credit: CBS)

At least 13 units were evacuated during the fire.

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Editor’s Note: The name of the witness has been removed from this story at that person’s request.