An investigation has begun after a Grade II listed bridge in Birkenhead was “seriously damaged” by fire.

Police want to trace six young people wearing hooded tops who were seen in Birkenhead Park between 02:10 and 04:20 BST on Sunday.

The wooden Swiss Bridge was built when the park first opened in 1847 and had recently been repainted.

Wirral Council said “significant” structural reconstruction could cost up to £20,000.

Anyone with any information is asked to contact Merseyside Police on 101 or Crimestoppers