At least two people have been killed and eight others critically injured in a shooting on the campus of Brown University in Providence, Rhode Island, officials have said.
Final exams were taking place in the engineering building on Saturday afternoon when a shooter opened fire, Brown University provost Frank Doyle said.
Police said the suspect - described as a male dressed in black - left the building on foot and is still at large.
Officers searched the buildings of the Ivy League campus and sifted through trash cans for several hours after the shooting erupted.
Providence mayor Brett Smiley said a "shelter-in-place" was in effect for the area and urged people living near the campus to stay inside and not to return home until it is lifted.
"We have all available resources" to find the suspect, he said at a news conference.
Mr Smiley said a person who was initially thought to be involved in the shooting was detained but was later determined to have no involvement.
He said the eight wounded people were in critical but stable condition. He declined to say whether the victims were students.
Mr Smiley asked for prayers for the families of the victims, noting the coming Christmas holiday.
"It's going to be a difficult rest of the day, difficult days and months ahead as this community heals," he said.
President Donald Trump told reporters at the White House that he had been briefed on the situation, which he called
"terrible".
"All we can do right now is pray for the victims and for those that were very badly hurt," he added.
The shooting was reported near the Barus & Holley building, a seven-storey structure that houses the School of Engineering and Physics Department, according to the university's website.
It includes 117 laboratories, 150 offices and 15 classrooms.
Brown is a private university with roughly 7,300 undergraduate students and more than 3,000 graduate students.
Providence Council member John Goncalves, whose ward includes the Brown campus, said: "We're still getting information about what's going on, but we're just telling people to lock their doors and to stay vigilant.
"As a Brown alum, someone who loves the Brown community and represents this area, I'm heartbroken. My heart goes out to all the family members and the folks who've been impacted."
'I was hoping that no one's getting hurt'
Student Chiang-Heng Chien said he was working in one of the labs with three other students when they received a notification about a shooting nearby.
"We decided to turn the light off and close all the doors and hide under our desks, and wait for the next notification after the shooting," he told reporters.
The students hid under the desks for about two hours.
"I was hoping that no one's getting hurt and no one's dead," he said.
The students left the building when they received another notification, and security personnel moved in to search the facility.
Local media reports indicated that the manhunt was made more challenging by the large crowds in downtown Providence, where holiday shoppers and thousands of concertgoers were gathered.
According to officials, federal law enforcement and police from nearby cities and towns were helping with the search.
"We are a week and a half away from Christmas. And two people died today and another eight are in the hospital," Mr Smile said.
"So please pray for those families."
This breaking news story is being updated and more details will be published shortly.
Please refresh the page for the latest version.
You can receive breaking news alerts on a smartphone or tablet via the Sky News app. You can also follow us on WhatsApp and subscribe to our YouTube channel to keep up with the latest news.
(c) Sky News 2025: At least two dead and eight critically injured in US university shooting - as police hunt gunman
King 'deeply touched' by reaction to cancer 'good news' - as screening sites see traffic surge
Specialist teams and online investigators deployed across England and Wales to tackle 'national emergency' of violence against women and girls
Trump says US 'will retaliate' after three Americans killed in Syrian 'Islamic State attack'
Belarus pardons key opposition activist, among 123 prisoners, in exchange for US sanction relief
Two 17-year-olds die after car crashes into tree in Rotherham
Virginia Giuffre's family 'deeply disappointed' Met Police won't open probe into claims Andrew asked officer to investigate her
Israel says Hamas commander - who was one of the architects of the 7 October 2023 attacks - killed in strike
UK has seen longest period without migrants arriving on small boats since 2018, figures show
End of small boats crossings pause exposes fragility of migration debate