According to terror analyst Michael S Smith, a message circulated by a 225-member Whatsapp group called 'War news/Ummah news' read, "Oh Muslimeen when your brothers took revenge on the crusader nationals for the slaughter they are carrying out on the Muslims, they were shot on site by the the British Police."

The group was referring to the recent London attacks which accounted for at least 29 lives, apart from injuring dozens.

Questioning the Police's role, where the officers shot all three attackers in the recent London Bridge attack, the group said, "Then how come the Police never shot a Kaafir (atheist)," the message read.

Urging Muslims men to join the jihad, the message read, "Oh Muslims you need to wake up the war is starting now in your own streets outside your own Masajids (mosques). Your elders could be killed, your sisters could be attacked."

Meanwhile, Britain is treating the Finsbury mosque incident as a terror attack.

This is the third such instance in a span of a month.

The first attack of the two attack, which have been claimed by ISIS, took place in the Manchester Arena, following the conclusion of a pop concert by American singer Ariana Grande.

It killed at least 22 people as a suicide bomber detonated a bomb.

The second attack took place at the iconic London Bridge and the nearby Borough Market, where three terrorists first ploughed through people and later resorted to stabbing civillians, killing seven.

image: twitter.com/MichaelSSmithII