Three people were killed and three others injured Monday morning in a shooting outside a casino in Reno, the U.S. state of Nevada, local authorities said.

The Reno Police Department, along with multiple partner agencies, responded at 7:25 a.m. local time (1425 GMT) to the report of an active shooter at the Grand Sierra Resort and Casino located at 2500 East Second Street, said the department in a news release.

Police officers arrived on the scene within two and a half minutes.

The unidentified male gunman walked through a parking lot from the north and emerged at the casino's valet area, said Chris Crawforth, chief of the Sparks Police Department. Sparks is a nearby city east of Reno.

The gun of the suspect initially malfunctioned before he was able to shoot at a group of bystanders. Five people in the valet area sustained gunshot wounds. One victim was killed on the scene, and another died later at a hospital. Two of the five victims remained in critical condition and one was released from the hospital, according to Crawforth.

The suspect fled through the parking lot and exchanged gunfire with a security guard there. A third person who was driving through the parking lot was fatally shot by the suspect.

Officials said the suspect was struck by police gunfire and taken to a hospital, where he remains in critical condition.