Book link probed after petrol bomb

Two men were arrested outside a home in Lonsdale Square, in Islington, north London, on terror charges in the early hours of Saturday, while a third was detained outside a nearby Underground station.

Neighbours described seeing smoke and flames in the doorway of the house, and it is believed an accelerant was used to start the fire.

The property is the home and office of Martin Rynja, the director of Gibson Square, an independent publishing house which earlier this month announced it was planning to release The Jewel of the Medina in the UK.

The novel, by American author Sherry Jones, was pulled by publishers in the US over fears it would anger Muslims, while a publisher in Serbia withdrew it from the shelves after protests from local Islamic leaders, who said it insulted Mohammed and his family.

Detectives are understood to be investigating the possibility that the Lonsdale Square attack was motivated by Dutch-born Mr Rynja's association with the controversial novel.

Scotland Yard described the arrest operation as being "intelligence-led", rather than in response to an incident - suggesting police knew some kind of attack was possible, and allowed it to take place before making arrests.

A police spokesman said the health and safety of the public was their top priority, and officers have guidelines to follow to ensure this is maintained.

Residents in Lonsdale Square said armed police, assisted by fire-fighters, broke down the door of number 47.

Mr Rynja's next door neighbour Kevin Austin, 44, said he was woken up by police banging on his front door. He said: "All we heard was someone outside shouting get on the ground, get on the ground very, very loud and very forcefully. Then they shouted stop struggling, and we heard a van door closing and several cars speeding off."