SAN BERNARDINO, Calif. - Police estimate that at least 14 people have been killed and more than a dozen wounded in the shooting at a social services facility in Southern California.

Police believe the shooters were wearing "military-style" attire and may have fled in a dark-colored SUV. Officers said shots were later fired and a suspect was down at a dark-colored SUV, but it's not clear if that scene is related to the shooting.

One male suspect and one female suspect are dead. Another possible suspect was detained after he was seen running away from the building.

Authorities say 10 of the 14 people wounded the deadly shooting were taken to hospitals in critical condition.

Fire Chief Tom Hannemann says three people were in serious condition. Authorities say an additional 14 victims were killed in the gunfire at the Inland Regional Center in San Bernardino, 60 miles east of Los Angeles.

The chief says firefighters were on the scene within seven minutes of the 11 a.m. Wednesday call and transported all the injured by 11:30 a.m.

Police are searching a house in a near the scene. They say the suspects were well-prepared for the crime.

The president and CEO of the Southern California social services center says the shooting happened in a conference area where the San Bernardino County Department of Public Health was having a banquet.

Marybeth Feild of the Inland Regional Center was not at the facility but says she is in contact with many employees. She says they told her the shooting happened Wednesday during a banquet for the health department.

Police Chief Jarrod Burguan says up to three shooters entered the building and opened fire at the Inland Regional Center in San Bernardino, which works with individuals with developmental disabilities.

Burguan said the attackers came prepared with long guns, "were on a mission" and "came in with a purpose."

The attack was concentrated in one area of the building where most victims were shot, while hundreds of other people weren't injured.

Burguan says it's too early to say whether the attackers targeted that area or chose it out of convenience or at random.

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Triage units were set up in the area, and some people have been seen being wheeled away on gurneys. Others walked holding their hands in their air are being led away by authorities.

At least 10 people have been taken to hospitals for treatment. San Bernardino County announced on its Twitter account that six people were being treated at Arrowhead Regional Medical Center, which is run by the county. 

A spokeswoman for Loma Linda University Medical Center says four patients were taken to its trauma center. Spokeswoman Briana Pastorino says she didn't know their conditions. She says the hospital expects to get three more patients.

At a Shell gas station about a block from the shooting site, store manager Ana Fuentes says she hasn't gotten any instructions to stay inside but customers have told her about shootings at the Inland Regional Center. The center says on its website that it provides social services to people with developmental disabilities.

Terry Petit says he got a text from his daughter saying she was hiding after gunfire erupted at the social services facility in Southern California where she works.

Petit choked back tears Wednesday as he read the texts for reporters outside Inland Regional Center in San Bernardino.

He says she wrote: "People shot. In the office waiting for cops. Pray for us. I am locked in an office."

Police searched people filing out of a building with their hands up before they reunited with loved ones.

Ambulances and law enforcement vehicles are racing through the area with sirens blaring. Local police, the FBI and the Bureau of Alcohol, Tobacco and Firearms have also responded.

President Barack Obama was briefed on the shooting by his homeland security advisor. He has asked to be kept informed as the situation continues to develop.

San Bernardino is about 60 miles east of Los Angeles. 

.@SanBernardinoPD has confirmed 1to3 possible suspects.Multiple victims. #SBCSD &other agencies assisting. More info to come. #SanBernardino

— SB County Sheriff (@sbcountysheriff) December 2, 2015

This is a developing story. Please check back for updates as they become available.