People inside a 25-story Los Angeles residential building -- some in bathrobes, on the roof, and even one scaling the side of the building -- tried to escape flames and clouds of smoke Wednesday morning as more than 300 firefighters responded to the fire.

The Los Angeles Fire Department said the fire was reported about 8:30 a.m. at the Barrington Plaza apartment building in the Sawtelle neighborhood on the city’s west side. It was fully out by 10 a.m., officials said.

Two 30-year-old men were hospitalized, with one in grave condition and the other in critical condition, fire Capt. Erik Scott told reporters.

"The preliminary information is the most critically injured... were both in the unit of fire origin," Scott said.

Paramedics rushed four other patients -- a man, age 25, two women, ages 26 and 20, and a 3-month-old girl -- to hospitals for smoke inhalation. Medical personnel evaluated five other people at the scene.

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Fire officials initially said some people had jumped from the building but then clarified that two people contemplated jumping before firefighters rescued them, the Los Angeles Times reported.

Fire officials battled the flames in 40-mph winds and were able to knock down the flames by 10 a.m., according to the Times.

"This was a herculean effort by the members of the Los Angeles Fire Department," Fire Chief Ralph Terrazas said. "It takes a lot of coordination, and our resources did a good job."

The cause of the fire remained under investigation. Terrazas said an arson team was at the scene and the fire was deemed "suspicious."

Investigators initially said they had a suspect in custody but then rescinded their statement, KNBC-TV reported.

Helicopters rescued people from the roof of the building, Terrazas said at a news conference. A large inflatable bag was set up on the ground on one side of the building.

The fire originated on the sixth floor, then spread to the fifth, seventh and eighth floors. Firefighters were going door to door to check on people inside, but further evacuations may be necessary.

"Those hallways are black. They're charred. They're smoldering," Scott said. "Halfway through that hallway, our firefighters were forced on their bellies due to the significant heat when those windows were broken out and that really fueled the flames pushing at them."

The Los Angeles Police Department, the Los Angeles Sheriff's Office and the Santa Monica Fire Department were also on the scene, a news release said.

One person was at the tower's swimming pool when he saw smoke coming from a residence, KNBC reported. He said he ran to the lobby to report it.

"It was just a wall of black smoke," said Gavin Strauss, who lived in the building.

The tower did not have a sprinkler system, officials said. The Los Angeles Times reported after a 2013 fire at the same building that because it was built 52 years ago it wasn’t required to have one under state regulations.

Earlier the same morning, a windswept blaze damaged a 26-story office building three blocks away. About 50 people were evacuated from that building, where damage was mostly confined to the first and second floors, The Associated Press reported.

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Authorities said they were investigating whether both fires were related. That fire was first reported about 2:45 a.m., according to the news station. The blaze was put out by 4 a.m. local time, the LAFD said in a news release.

"We are looking at a connection between this fire here and the other fire that's three blocks away because they both erupted in close proximity," Scott said.

The Associated Press contributed to this report.