A female medical staffer at Olive View-UCLA Medical Center said an armed man confronted her early Thursday on the second floor of the Sylmar hospital, prompting an evacuation and search for the suspect that lasted several hours.

The hospital on Olive View Drive was cleared for normal operations about 12:30 p.m. Thursday after Los Angeles County Sheriff’s Department deputies searched the facility for hours after receiving reports of what was called a possible active shooter about 9:20 a.m.

No shots were fired, and no injuries were reported.

Sheriff’s officials said a female member of the medical staff reported that she was confronted by a man wielding a weapon on the second floor of the hospital.

The woman ran for safety and reported what she saw to hospital staff, but the man disappeared.

The hospital was evacuated, but no suspects were found, deputies said.

#LASD debriefing earlier rapid response to hospital after sighting of a gunman was reported. Area is all clear. Investigation continues. pic.twitter.com/Vd91v41Z3b — LA County Sheriff's (@LASDHQ) October 19, 2017

Hospital officials said that while the evacuation was underway, patients in the intensive care unit remained inside the building under guard.

Sheriff’s officials said they planned to check hospital surveillance camera footage in hopes of identifying the suspect.

After the call came in this morning, a heavy presence of patrol units could be seen racing west along the 210 Freeway, toward the hospital, which has nearly 400 beds and serves the San Fernando and Antelope valleys.

10/19/17 at 9:20 a.m. poss person w/ gun seen at Olive View UCLA Medical Center, #Sylmar. No Active Shooter. #LASD personnel on-scene. — LA County Sheriff's (@LASDHQ) October 19, 2017

The report prompted a lockdown of patients and staff as the facility and its grounds were searched.

Some people were questioned as possible witnesses or suspects, and Olive View Drive was shut down.

Lois Ramirez of the hospital told KNX Newsradio that the facility was placed on lockdown after “the sheriff’s department had called in what we call a ‘code silver.'”

“That immediately prompted us to do a lockdown of all patients and staff in the hospital,” Ramirez said shortly after 10 a.m. “We (will) remain on lockdown until we get an all-clear from the sheriff’s department … .”

Ramirez said patients who had come in for procedures or tests were told to remain in the clinic until cleared to leave. Anyone with appointments, however, would not be allowed into the facility “until the situation is cleared,” Ramirez said. “There is no active shooter,” she said.

Dozens of patients and hospital workers could be seen leaving the building, walking to a parking lot holding area as sheriff’s investigators released them from the facility.

Los Angeles city and county firefighters helped tend to the needs of patients and others who were evacuated from the hospital, said LAFD spokeswoman Amy Bastman.

A total of 11 patients were transported to other local hospitals, Bastman said. Of those, four were taken by LAFD ambulances.

City News Service contributed to this report.