A manhunt is under way after two students were killed and nine other people were injured in a shooting at Brown University in Rhode Island.

Officials say the gunman opened fire in a classroom at around 16:00 local time (21:00 GMT) on Saturday at the Barus and Holley engineering building on the eastern end of the Ivy League university's campus, where final exams were taking place.

Officials from Rhode Island Hospital said most of the injured are in a "critical but stable" condition, and that the hospital is "in lockdown" while the suspect remains at large.

A shelter in place warning remains in place for the greater Brown University area.

The identities of those killed or injured have not yet been released by officials.