American conservative commentator Charlie Kirk has been killed after being shot during an event in Utah.

It occurred on Wednesday at Utah Valley University while the 31 year old Kirk was on stage.

Graphic videos of the shooting were widely circulated on social media.

Officials say the suspect is unknown and at large.

State police issued a statement on Wednesday night saying that two men had been detained and one was interrogated by law enforcement, but both were subsequently released.

"There are no current ties to the shooting with either of these individuals," the statement said.

"There is an ongoing investigation and manhunt for the shooter."

Utah’s governor said it was a sad day for the state, calling it a political assassination.

People of all political stripes are condemning the shooting.