The FBI and ATF are on the scene of a shooting at a San Bernadino, California office park on Wednesday. The suspect apparently got away in a black Yukon.

12 people are reported dead and 20 are wounded following the shooting at a clinic that treats patients with developmental disabilities. A Christmas party was underway at the Inland Regional facility at the time of the shooting (see video below).

Witnesses described walking past bodies on the floor as they ran out of the building.

The shooting took place at a facility that provides services to people with disabilities. There is also a Planned Parenthood at the location. According to CNN, the Planned Parenthood was not the target of the shooting.

Witnesses tell police one heavily armed suspect walked into a conference room in one office building and opened fire around 11 a.m. PST (2 p.m. EST).

CNN quoted the LA Times that reports 3 heavily armed suspects were involved in the shooting. One suspect is believed to have barricaded himself inside.

There are many conflicting reports about the number of shooters.

The suspect is described as heavily armed men, wearing body armor and a mask. He reportedly left the scene in a black SUV with tinted windows.

Police are searching for the black SUV that slowly drove away after the shooting.

UPDATE: The county health department rented out a conference room at the Inland Regional Center for a Christmas party. Police believe the health department employees were targeted by the gunman (or gunmen), not employees of the Inland Regional Center.

A black Yukon was found abandoned several miles away from the site of the mass shooting. The area around the SUV has been cordoned off by police.

UPDATE 2: 14 dead and 14 reported injured in mass shooting.