A 19-year-old man has turned himself in after an armed assault caused UMass Amherst to be put on lockdown for two hours on Thursday, Framingham police said.

William McKeown is expected to be arraigned on assault and battery charges with a deadly weapon, simple assault, as well as battery and armed robbery. There were no shots fired but one male victim suffered a head laceration, WCVB reported. Officers had previously seized a car parked on Water Street that they suspected of being linked to the incident.

The Amherst campus was under a "shelter in place" order on Thursday as police investigated after a man was reported in Pierpont Hall with a gun. A second man was mentioned in the school's emergency alerts, according to WCVB. ​

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The school posted on their Facebook late Thursday night that the assailants weren't believed to be one of their students. UMass police said the assault is not believed to be random.

Video evidence showed authorities that the two suspects were provided access willingly by a UMass student into Pierpont Hall, according to Metro West Daily News

It remains unclear if police are still looking for a second person.