(AP) -- One or more gunmen opened fire Wednesday at a Southern California social services center, shooting multiple people, authorities said.

Several law enforcement agencies converged on the scene in San Bernardino and were searching for the suspects. Triage units were being set up in the area.

Some people were seen being wheeled away on gurneys after gunfire erupted at the Inland Regional Center. Others walked quickly from a building with their hands in the air and were searched by officers before being reunited with loved ones.

Police were working to secure the scene in the inland region about 60 miles east of Los Angeles, Sgt. Vicky Cervantes said. No arrests have been made.

Terry Petit said his daughter works at the center, and he got a text from her saying she was hiding in the building after hearing gunshots.

Petit choked back tears as he read the texts for reporters outside the center. He said she wrote: "People shot. In the office waiting for cops. Pray for us. I am locked in an office."

At a Shell gas station about a block from the shooting site, store manager Ana Fuentes said there was a flood of police activity in the area.

"There's maybe like 150 cops going toward Hospitality Lane," she said, as sirens echoed in the background.

She said she hadn't gotten any instructions to stay inside but that customers coming in told her about the shootings at Inland Regional Center.

The center says on its website that it provides social services to people with developmental disabilities.

The city of San Bernardino has struggled to rebound after declaring bankruptcy in 2012. The city of about 214,000 is in the two-county inland region that was hit hard by the Great Recession.

The area where the shooting occurred is along a main city road that fronts a city golf course and recreation center.