A standoff with an armed man at the University of Connecticut in Groton that forced the evacuation of the campus is over after the man committed suicide, according to local reports.

Police had been negotiating for hours with the man, who had crawled beneath a dock on the premises.

“As the subject was pointing the weapon towards himself and towards others,” Connecticut Police Lt. Paul Vance said, “troopers deployed less-than-lethal equipment in an effort, again, to disarm the subject. Again, it was not successful.”

They attempted to stop the gunman by talking to him on his cell phone and tried to distract him by using bean bags, flash grenades and a tactical vehicle, NBCConnecticut.com reported.

The man’s family had called Groton, Conn., police around 5 p.m. Monday, saying he was despondent and armed, police said. A few hours later, he drove his Jeep onto the university campus.

Police spotted the gunman just after 10 p.m. ET Monday, threatening to hurt himself.

At around 2:15 a.m. ET, police said they had set up a perimeter around him.

Police ordered an emergency evacuation of the entire campus, and a brief emergency alert was sent out and posted to the university’s website.

“He doesn’t appear to be a threat to others, but we want to secure his safety,” University of Connecticut spokeswoman Stephanie Reitz said during the standoff.

Police said the man was 30 years old, and they won’t release his name until the family is notified.

A group of high school students was on the campus for a summer program, but the students remained in another building on the opposite side of campus during the standoff. Reitz said very few people were believed to be on campus because of summer vacation.

The school reopened at 8 a.m. ET Tuesday, but the investigation continues. 

NBC Connecticut and The Associated Press contributed to this report.

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