The Department of Buildings says further investigation is needed to determine the cause of the collapse of a four-story building in Clinton Hill Sunday.

At a press conference Monday afternoon, DOB Commissioner Robert LiMandri says weather could have been a factor in the collapse of the late 19th century building.

The investigation is also centering around the building's owner, William Sang, and whether he properly maintained the property.

The New York City Fire Department says several people were inside the building at 493 Myrtle Avenue when bricks started falling, but everyone made it out before the building came down.

Four people suffered minor injuries.

"By the time, it happened within five seconds, by the time I grabbed my phone, my kitchen was crumbling in front of me," said a resident. "I ran out the door and I slid down the stairs and that's where I got the bruise from. When I got to the front door, that's [when the whole thing collapsed]. That's how quick, it happened within 10 seconds."

"Luckily none of our units were yet in the building," said FDNY Chief Ed Kilduff. "They were preparing to enter the building."

A construction crew had been working on the building, which had a history of violations.

Last month, the city issued a violation to Sang for not maintaining an exterior wall, which had vertical cracks. An engineer determined it was safe for people to inhabit the building was renovations were made.

"The owner is the responsible party," said LiMandri. "They are strictly liable to make sure they take care of the buildings and make sure the residents of those buildings can be there safe. This Buildings Department will move forward and take action against any owner, contractor that does not follow the rules and regulations in the City of New York."

Sang was due in court Monday morning for a hearing on that violation. The DOB says the owner had taken actions, hiring M&R Construction to correct the problems. However, it will continue to look into the owner's care of the building.

"The Buildings Department came and gave us violation," Sang said. "We had a company come out and asses it; they removed the stucco. They were doing work."

Six surrounding buildings were evacuated so inspectors could check for structural damage.

The Buildings Department says residents of 485, 487 and 499 Myrtle Avenue have been allowed to return to their homes; 497, 491, and 489 Myrtle Avenue remain vacant. Eighteen adults and four children remain homeless and have been registered with the Red Cross.

The DOB commissioner says both 491 and 493 Myrtle Avenue will be demolished.

Councilwoman Letitia James says the city must do more to protect the area's buildings.

"A lot of these buildings are structurally vulnerable, so they cannot be compromised," she said. "Whenever there is any work, we have to make sure the contractors are doing it according to the law and under the supervision of the Department of Buildings."

LiMandri said the DOB is investigating all parties involved, including the engineer, inspectors, owner and contractors, to make a final determination about the cause of the collapse.