Thirteen people were wounded when gunfire erupted during a rap music concert at a nightclub in Tempe in the US state of Arizona, police said early Saturday.

"At this point, Tempe police officers and detectives have identified 13 shooting victims from the incident," Tempe Police Department spokesman Sergeant Steve Carbajal said in a statement.

"Two victims are in serious condition at local hospitals, and none of the victims were fatally injured."

The shots were fired shortly before midnight local time Friday (0700 GMT Saturday) at the popular Clubhouse Music Venue, which entertained the crowd with a rap music concert, Carbajal said.

He said witnesses had reported two black males in dark-colored clothing fleeing the scene on foot after the shooting.

"Those individuals have not been located at this time," Carbajal said.

"Tempe police detectives are currently on scene investigating what led up to the shooting and working on identifying the suspects."

The shooting came just days after a teenager identified as TJ Lane opened fire at a Chardon, Ohio high school, killing three people and wounding two.

Lane allegedly fired 10 shots from a .22-caliber handgun Monday on a group of teenagers in the school cafeteria, hitting some in the head at almost point-blank range while other students ran for their lives.

He then fled the scene, chased by a teacher, before giving himself up to bystanders a short distance away and being apprehended by police.

The deadliest school shooting in the United States was the 2007 massacre at Virginia Tech University that left 33 people dead.

The worst high school shooting was in 1999 at Columbine High School in Colorado, where two students killed 12 fellow students and a teacher. (AFP)