LONDON (AP) Police say two children have died and nine people have been injured in a stabbing in northwest England.

Merseyside Police said a 17-year-old boy was arrested and a knife seized after the bloody attack Monday in Southport, a seaside town near Liverpool.

Police say the attack happened at a community center where a Taylor Swift -themed dance and yoga event for primary school-aged children was held. A nearby shop owner says he saw between seven and 10 bleeding children run from the building.

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