A stabbing in northwest England killed 2 children and injured 9 others.

LONDON: A stabbing at a children’s dance class in northwest England on Monday killed two children and injured nine other people, police said. A 17-year-old boy was arrested and a knife seized after the bloody attack, police said.

A witness described seeing bloodied children running from a community center where a Taylor Swift-themed dance and yoga event for children aged about 6 to 11 was taking place in Southport, a seaside town near Liverpool. An advertisement for the event promised “a morning of Taylor Swift-themed yoga, dance and bracelet making.”

Prime Minister Keir Starmer called the attack “horrendous and deeply shocking.”

Merseyside Police said officers were called at about noon to an address in Southport, a seaside town of about 100,000 people near Liverpool. It called it a “major incident” but said there was no wider threat to the public.

Detectives were not treating the attack as terror-related, the force said.

The suspect, who has not been identified, lived in a village about 5 miles (8 kilometers) from the site of the attack, police said.