British authorities are investigating a stabbing attack that occurred Saturday evening aboard a passenger train in Cambridgeshire, England, leaving nine people with critical injuries.

According to British Transport Police (BTP), “multiple people have been stabbed” on a train bound for Huntingdon. Armed officers were deployed to Huntingdon station, which was subsequently closed.

Armed officers were seen running along the platform at Huntingdon station towards the train carriages after multiple people were stabbed on board.