A male was detained Monday after reports of a collision with people in Liverpool, England, police said. 

Police were called to the scene in the city center, more than 200 miles northwest of London, at about 1 p.m. ET (6 p.m. local time).

There were reports of a car colliding with “a number of pedestrians,” the Merseyside Police said on social media. “The car stopped at the scene and a male detained.”

Liverpool was holding a victory parade for its soccer team Monday. Tens of thousands of fans had gathered in the city center, lining the streets to watch Liverpool’s players display the Premier League trophy, The Associated Press reported.

Police did not immediately give information on casualties. 

Photos from the scene showed multiple ambulances and first responders, an ambulance service said it was responding to the incident.

North West Ambulance Service “is supporting an incident in Liverpool city centre, following reports of a road traffic collision,” the organization said in a statement. “We are currently assessing the situation and working with other members of the emergency services. Our priority is to ensure people receive the medical help they need as quickly as possible.”

U.K. Prime Minister Keir Starmer wrote on social media that “the scenes in Liverpool are appalling.”

“My thoughts are with all those injured or affected,” he wrote. “I want to thank the police and emergency services for their swift and ongoing response to this shocking incident.”

This is a developing story. Check back for updates.