At least two people were killed and eight more critically injured in a shooting Saturday afternoon at Brown University in Rhode Island, authorities said. The suspect is still believed to be at large. 

In a news conference Saturday evening, Providence Mayor Brett Smiley said that the shooting was reported in the Barus & Holley engineering building a little after 4 p.m. local time. 

Smiley said that at least two people were killed and eight more taken to Rhode Island Hospital in "critical but stable" condition. The hospital later said in a statement that six of the patients were in "critical but stable condition," one was in critical condition, and another was in stable condition. 

"Those are the only injuries or casualties that we know at this time," Smiley said, adding that "these numbers may change, we are still in early hours."

The school said that final exams were taking place in the building at the time of the shooting.   

Smiley said that no arrests had been made, and a shelter-in-place was in effect for the Brown University area. No weapons have been recovered, Providence Deputy Police Chief Tim O'Hara told reporters. 

O'Hara told reporters the suspect was only described as a male dressed in black. He escaped from the engineering building following the shooting, O'Hara said. It was unclear how the suspect had entered the building, but the suspect exited on the Hope Street side.

Police are working to release images of the suspect to the public, a law enforcement source told CBS News.

Officials cleared the building but did not find the suspect, and no weapon has been recovered.

"If you live on or near Brown's campus, we are urging you to stay home and stay inside," Smiley said. 

A university alert told students to lock doors, silence phones and stay hidden until further notice. "Our Department of Public Safety has been working closely with law enforcement and has been informed that the suspect is still at large and the situation remains active," Brown University President Christina H. Paxson said in a statement Saturday evening. 

She said the school continues to be in lockdown and community members should remain sheltered in place with all doors locked.

School public safety had initially reported that a suspect had been taken into custody before retracting that statement. 

"There was an individual who was preliminary thought to be involved, but was later determined to have no involvement," Smiley told reporters. 

President Trump wrote in a Truth Social post that he had been briefed on the shooting. 

"God bless the victims and the families of the victims!" Mr. Trump said. The president also initially wrote that a suspect was in custody, but in a follow-up post, wrote, "The Brown University Police reversed their previous statement — The suspect is NOT in custody."

The FBI confirmed in a statement to CBS News that it was assisting "our law enforcement partners in Rhode Island with any and all available resources." 

The Bureau of Alcohol, Tobacco, Firearms and Explosives also posted on X that it was sending agents to the school. 

"The unthinkable has happened," Rhode Island Gov. Dan McKee said at the news conference.