An armed 19-year-old man opened fire just outside a graduation ceremony in Richmond, Virginia, killing at least two people and leaving five others injured, police said Tuesday.

The suspect, who was arrested, faces two counts of second-degree murder along with other offences, interim Richmond Police Chief Rick Edwards said addressing a press conference. The names were not immediately revealed however, the former was said to be graduated Tuesday.

According to the police, a 31-year-old injured had life-threatening injuries but the other four males, ages 14, 32, 55 and 58, had non-life-threatening injuries.

The motive behind the shooting in Richmond Virginia was not known but they maintained that the suspect knew “at least one of the victims.”

Richmond Police acting chief Rick Edwards had earlier said that two suspects were detained, but Tuesday night he clarified that one of the two people under arrest was not believed to be involved in the shooting.

School board member Jonathan Young told Richmond TV station WWBT that graduates and other attendees were leaving the building when they heard about 20 gunshots in rapid succession.

“That prompted, as you would expect, hundreds of persons in an effort to flee the gunfire to return to the building,” Young said.

“It materialised in a stampede,” he said.

Edwards said that four handguns were recovered, but at least one belonged to the second individual who is not believed to be involved.

“Off-duty officers working security inside the ceremony immediately responded to the scene and found the shooting victims,” Edwards said.

“Virginia Commonwealth University security detained the suspect after he left the scene,” added Edwards, mentioning that “no police officers were injured or fired their weapons during the incident.”

Acting Chief Edwards also remarked that a number of people were treated for different injuries, including two people from falls, a 9-year-old girl who was hit by a car during the shooting, and three people who were treated for anxiety.

Edwards also underlined that there was no ongoing threat to the community.

A spokesperson from Richmond Public Schools said: “The graduation ceremony would be rescheduled. This incident occurred toward the end of the Huguenot High School graduation and we have cancelled the Thomas Jefferson High School graduation scheduled for later tonight. It will be rescheduled soon.”

US Representative Jennifer McClellan, from Virginia’s fourth congressional district, including Richmond, said in a statement, “Tonight’s celebration turned into every parent’s worst nightmare. As the mother of two school-aged children, I cannot fathom the profound heartbreak, sense of loss and trauma these families are experiencing.”

“The gun violence epidemic is a public health crisis that we must address. We cannot continue to live in fear,” McClellan added.