Watch: Footage shows masked figure pacing outside house raided in Southport
ITV News has obtained footage of an individual pacing in front of a house that was later raided by police in Southport.
An individual wearing a green hoodie and a face mask can be seen walking back and forth outside the front door of a house.
Later footage shows several police cars and a group of officers, including some who are armed, appearing at the same house.
It follows the death of two children in a knife attack in Southport on Monday, which left nine other children injured.
Merseyside Police confirmed a 17-year-old boy has been arrested.
The teenager, from the village of Banks, and originally from Cardiff, is currently being questioned on suspicion of murder and attempted murder.
A witness said he called police to an address in Hart Street behind which is The Hart Space studios.
One of the events listed at The Hart Space at the time of the stabbings was a Taylor Swift-themed yoga class for children in school years two to six, aged between six and 11.
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