The campus of a liberal arts college in Maine was put on lockdown early Saturday morning after a shot was fired in a student housing complex during what one student called a massive annual party.

Colby College said no students were hurt during an altercation that involved a firearm being discharged at the Alfond Senior Apartments on the campus in Waterville, Maine.

No Colby students were injured. The suspect is a 24-year-old Waterville man not affiliated with the college. Police were continuing to look for others involved, the school said in a statement.

Police did not perceive imminent danger to the campus community, but asked students to stay in place throughout the night out of an abundance of caution, the college said.

Normal operations were expected to resume in the morning, the school said.

An email sent to the student body by Interim Dean of the College Barbara Moore at 2:21 a.m., which was shared by a student, said the Waterville Police Department “have a person in custody who attended events there and fired a gun.”

“We urge you to shelter in place until we have additional information that the campus is entirely safe,” wrote Moore, who did not immediately respond to an email from The Associated Press.

In a statement issued Saturday, Waterville interim Police Chief William Bonney said officers were called to the college around 1:30 a.m. Saturday after receiving a report of shots fired on the Colby campus.

When police arrived they found the 24-year-old man on the ground being treated for injuries to his head. Police say the man got into an altercation with two other men. None of the three were Colby students.

The injured man fired two rounds from a 9mm handgun into the hallway walls without causing any injuries. He was treated for his injuries at a hospital then arrested and charged with reckless conduct with a dangerous weapon. He’s due in court on Monday.

“It is very fortunate that no innocent bystanders were hurt by this reckless behavior,” Bonney said in the statement. “I feel terrible for the students and parents who had to go through the trauma of this event, worrying that one of their loved ones may be hurt or worse.”

Landon Kissell, an 18-year-old freshman from Manhasset, New York, said he left campus by car “just to play it 100% safe” about five minutes after receiving a message about the incident at 1:49 a.m.

“There was definitely some scramble to find a secure location but since everyone was inside already due to the temperature that most people either stayed right where they were or went to the next building over and locked themselves there,” Kissell said.

Alfond apartments, where the shot was fired, was the site of what Kissell described as “a massive party night” that takes place for about 24 hours every year on St. Patrick’s Day. The holiday is on March 17 but the party, known as “doghead,” was moved up by a week this year because the holiday falls during Colby’s spring break, he said.

Kissell first learned of the lockdown from his dormitory resident assistant, who sent a text to students in the Sturtevent residence hall.

Kissell did not initially see the email from Moore or another from a student government leader who told students to remain in place.

“I never saw those emails until just now because who would think to check their email in a situation of panic right?” Kissell said at 3:25 a.m. from his car in the state capital of Augusta, about 20 miles (32 kilometers) south of the Colby campus.

Colby, founded in 1813, is the 12th oldest liberal arts college in the U.S., according to the school’s website.