A gunman went on a terrifying rampage in a gay bar and the surrounding streets in Oslo on Saturday, killing two people and injuring more than 20 on the day the city’s LGBTQ community was due to celebrate its annual Pride parade.

The attack took place in the early hours, with victims shot inside and outside the London Pub, a well-known gay bar and nightclub open since 1979, as well as at one other bar in the centre of the Norwegian capital.

“Many people were crying and screaming, the injured were screaming, people were distressed and scared - very, very scared,” said Marcus Nybakken, 46, who had left the London Pub shortly before the shooting and returned later to help.

“My first thought was that Pride was the target, so that’s frightening.” Journalist Olav Roenneberg of public broadcaster NRK said he was in the area at the time and saw a man arrive with a bag, take out a gun and start to shoot:

“Then I saw windows breaking and understood that I had to take cover.” A suspect, a 42-year-old Norwegian citizen of Iranian origin, was detained minutes after embarking on the shooting spree, according to police who said they believed he acted alone.

Two weapons, including a fully automatic gun, were retrieved from the crime scene, they added. “There is reason to think that this may be a hate crime,” police said. “We are investigating whether the Pride was a target in itself.”

The suspect is believed to be a radicalised Islamist who has a history of mental illness, Norway’s PST intelligence service said on Saturday. The suspect, who was not named by police, has been known to security services since 2015, the PST added.