Police officers on patrol over the weekend came upon a man down on a St. Paul sidewalk following a deadly assault, officials said Monday.

The discovery of 30-year-old Peter Nguyen, of Coon Rapids, was made about 1 a.m. Saturday near Case Avenue and Arcade Street, said Sgt. Mike Ernster.

"Officers quickly realized that the person was unconscious and not breathing," Ernster said.

The officers began CPR before medics took the man to Regions Hospital, where he died shortly afterward, Ernster said.

Officers secured the scene and began looking for witnesses and any video surveillance that may have captured the encounter.

No arrests have been made, and the Ramsey County Medical Examiner's Office has yet to release the man's identity.

Preliminary information "indicates that the victim may have been in an altercation with other people nearby and assaulted before officers found him," the sergeant said.

Anyone with information about this incident is being asked to contact police at 651-266-5650.