A storm pummelled concert-goers at Red Rocks Amphitheatre near Denver in the US with golf ball-sized hail, sending them running for cover, injuring dozens and forcing the cancellation of the show’s headliner, Louis Tomlinson.

Up to 90 people were treated for non-life-threatening injuries caused by Wednesday night’s storm, including seven who were taken to hospital, West Metro Fire Rescue said.

Some were hurt by the hail and others were hurt while trying to get away from the storm, sustaining injuries such as lacerations, bruises and broken bones, spokesperson Ronda Scholting said.

The hail piled up like snow in some spots in the amphitheatre.

The show was initially delayed because of the weather, with fans told to take shelter in their vehicles, according to tweets from the venue, which was carved out of a sedimentary rock formation in the foothills. It was later cancelled.

Beth Nabi, 44, had flown to Denver from Dublin to watch one of her favourite musicians perform at the famous venue.

At around 7.15pm, she said could see lightning and thunder approaching in the distance.

As the weather worsened, concert-goers were encouraged to seek shelter, but not wanting to give up hope on seeing former One Direction member Tomlinson, Ms Nabi stuck around.

She said the hail started falling while she was in a bathroom and that the space quickly filled up with other concert-goers who were trying to escape the falling ice.

“I came out of the bathroom stall to a bathroom filled with as many people who could cram in there, all seeking shelter from the hail,” she said.

The storm lasted about 10 minutes before she could leave the bathroom and see all the hail covering the ground.

“The hailstorm was just crazy. It was apocalyptic. It was fast,” she said.

Hail covering a walkway at the US concert venue
Hail covering a walkway at the US concert venue (West Metro Fire via AP)

To cap things off, she returned to her rental car to find its windshield cracked in several places. She said she is anxiously waiting to hear on when the concert will be rescheduled.

“I am gutted it didn’t go on,” she said. “’I’m hoping we get some news on when it can be rescheduled, and I hope I can make it because I was so looking forward for the experience at that venue.”

Tomlinson tweeted that he was “devastated” about the cancellation and promised to return.

“Even though we didn’t play the show I felt all of your passion! Sending you all love!,” he said.