Police in Salem, Massachusetts are looking for seven people who placed an unknown explosive device in The Rainbow Times news box early Tuesday morning.

In this surveillance video uploaded by Salem Police the seven individuals can be seen wearing black and walking towards the news box. Five of them leave while two remain to detonate the device.

Police said they received several calls after the explosion was heard up to a mile away.

Salem Mayor, Kim Driscoll said: ‘I am sad and upset about this incident, which based on the video surveillance footage appears to be targeting the Rainbow Times, an LGBT friendly news outlet.’

‘Salem is a community that has worked hard to be a place of progress and unity. This cowardly attack runs contrary, not simply to that work, but to what it means to be a city whose very name means peace.’

‘We are a community that supports each other as neighbors and, even in the face of violence and hatred, today should be no different. Fear and hate may cloud the hearts of those committing this act, but it will never, ever characterize this community. Salem is the City of peace.’

Some comments on Facebook suggest it was just ‘kids having fun’ while others see it as a hate crime.

Driscoll said Salem Police are working with The Rainbow Times in trying to find the vandals.

They ask the public to call Salem Police Detective Kevin St. Pierre at 978-744-0171 ext.179 with any information about the attack.