More than 400 law enforcement personnel were deployed on Saturday as police sought the suspect in a shooting at Brown University in Rhode Island that left two students dead and another nine people wounded at the Ivy League school, Reuters reported Sunday, citing local officials.

The university in Providence remained in lockdown hours after a suspect with a firearm entered a building where students were taking exams. Officials do not believe there is any “specific, ongoing threat” from the suspect, Providence Mayor Brett Smiley said late Saturday.

Streets around the campus were packed with emergency vehicles, and security was heightened around the city as law enforcement agencies sought the gunman, who has not yet been identified, officials said.

Officials released a video of the suspect, a male possibly in his 30s and dressed in black.

The gunman escaped after shooting students in a classroom in Brown's Barus & Holley engineering building, where outer doors had been unlocked while exams were taking place, officials said.

As news of the shooting spread, the school told students to shelter in place.

Rhode Island Governor Daniel McKee vowed that the shooter would be brought to justice. “We're going to make sure that we catch the individual that brought so much suffering to so many people.”

The search for the suspect was complicated by throngs of holiday shoppers and thousands of people attending concerts and events on a weekend night, local officials told reporters.

Compared to many countries, mass shootings in schools, workplaces, and places of worship are more common in the U.S., which has some of the most permissive gun laws in the West.