WEST LONG BRANCH -- A Monmouth University football player has been arrested in the attempted armed robbery that prompted a campus lockdown Tuesday night, authorities said.

Keith Williams, a freshman offensive lineman for the Hawks who played high school football in Maryland, was charged with first-degree armed robbery, Monmouth County Prosecutor's Office spokesman Charles Webster said.

Williams, 18, of Baltimore, Maryland, was suspended from the football team indefinitely, athletics department spokesman Greg Viscomi said.

Two students reported that a man wearing a hooded black sweatshirt and a stocking mask approached them at 9:20 p.m. and pulled out a handgun, according to a statement on the university's website.

The man demanded their cell phones, but the two women turned and fled the scene, the university said. The suspect then fled to the north side of campus through an underpass.

An investigation by the Monmouth University Police Department and Monmouth County Prosecutor's Office was launched after one of the victims called 911, Webster said.

The North Campus was placed on lockdown for two hours as police scoured the area for the weapon. Police found the weapon, which was an imitation handgun, just before midnight.

Williams was arrested inside an on-campus dorm, Webster said. He was taken to the Monmouth County jail and bail was set at $100,000 with no 10-percent option.

Monmouth University officials did not immediately respond to a request for comment on Wednesday afternoon.

Classes resumed on a normal schedule on Wednesday, the university announced.

Alex Napoliello may be reached at anapoliello@njadvancemedia.com. Follow him on Twitter @alexnapoNJ. Find NJ.com on Facebook.