FULLERTON – SWAT officers went room by room through Cal State Fullerton’s five-story Mihaylo Hall late Wednesday, searching for a robbery suspect they presumed was armed while checking on students and staff members who had taken shelter in classrooms.

Authorities searched past 10 p.m. with no sign of that man or a second suspect they believed was also in the area. Three others were arrested after an armed robbery in Moreno Valley and a police pursuit into Fullerton that hit speeds of 120 mph.

The campus lockdown ended just before midnight and classes were to resume Thursday morning as scheduled, officials said.

Click here to watch a video about the lockdown.

It was not immediately clear how many people had been in the classrooms at Mihaylo Hall, although officials said there could have been several hundred. Police had begun easing their lockdown orders around 10 p.m., letting people out of the building but checking their IDs as they left.

Officers cleared Mihaylo Hall shortly after 10 p.m., and more than two dozen SWAT officers filed out of the building. Police said they were turning their focus to other buildings, several hours after the sequence of events that locked down the campus began in a Moreno Valley jewelry store.

Witnesses reported that five men armed with handguns and wearing ski masks forced their way into the jewelry store around 3 p.m. and shot a clerk during the robbery. The clerk was rushed to Riverside County Regional Medical Center; he was described as being in stable condition.

Minutes after the robbery, the California Highway Patrol began pursuing a charcoal-colored two-door Lexus identified as the getaway vehicle. The high-speed chase ended across the street from Cal State Fullerton, when the Lexus crashed into a parked car.

Five men got out and scattered, police said, three running from the campus and two running toward it. Officers quickly captured one suspect on campus and another nearby. A third carjacked a vehicle, police said, kicking off another pursuit that ended at a baseball field in Watts, where the man was taken into custody.

One man who fled from campus remains on the loose, and police said they don’t know where he is. “If he’s outside our perimeter, hunkered down, he isn’t as much of a risk” as the other suspect thought to be hiding on campus, Fullerton police Sgt. Jeff Stuart said.

Police said that man was last seen in Mihaylo Hall, a classroom complex that houses the university’s business school.

Cal State Fullerton officials announced a campus lockdown on the school’s Twitter feed around 4:30 p.m., noting that there was a “possible dangerous suspect on campus.”

Campus officials advised students and campus visitors who were outside college buildings to leave the campus and for those inside to remain in place.

“They are going under the assumption that (the suspects) are armed and dangerous,” Stuart said.

Witnesses reported seeing snipers set up at businesses nearby as three SWAT teams entered Mihaylo Hall to begin the search. Nutwood Avenue was closed, and a crowd of about 100 students and workers gathered across the street from campus to watch the police.

Police said there were no gunshots fired, and no injuries had been reported.

All classes were canceled for the remainder of the day, spokesman Chris Bugbee said.

Officials at Cal State Fullerton estimate that fewer than 10,000 students were on the campus around 4 p.m. when the incident started.

“Right now, everybody is locked in and checking the television and the Internet, waiting to see what happens next,” Bugbee said.

Students reported a confusing scene as authorities instituted the lockdown and ordered some out of the campus buildings. Officers were reportedly going building to building, asking people to leave as soon as possible as police surrounded buildings where alarms were sounding and a helicopter hovered overhead.

University officials posted information for students in Storify form.

City News Service and The Associated Press contributed to this report.

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