Police in London are investigating a disturbing incident involving crosses that were painted on Jewish homes in a substance that appeared to have been blood.

A number of houses on a street in Stamford Hill, a district of North London with a large Orthodox Jewish population, were marked with a single cross daubed alongside the mezuzot on the doorframes.

Pictures of the vandalism were circulated online by the Shomrim, a Jewish community defense group.

The group called the vandalism a “hate crime” and “antisemitism” and claimed the perpetrator “appears to have used blood.”

“This attack bears similarities and invokes comparisons with actions by the KKK,” Rabbi Hershel Gluck, a spokesman for the Shomrim, declared.

However, local police took to social media to play down the possibility of a hate crime having been committed.

“Officers have spoken to the residents of these properties,” police in the London borough of Hackney stated on Twitter. “We understand it’s likely that a local man who is well known to residents and suffers with mental ill health may be responsible. Local officers are aware and will ensure the matter is addressed appropriately.”