An explosive device, thought to be a nail bomb, exploded outside a Liverpool school today while hundreds of children were in the building.

Police said the “despicable” attack appeared to be timed to coincide with the end of the school day.

The bomb exploded underneath a teacher’s vehicle in the car park of St Edward’s College, police are hunting for a man seen running away from the school.

Nobody was injured by the explosion that was detonated shortly before 3pm, just 10 minutes before the children were due to leave for the day.

The independent Christian school, who’s motto is “Courage through faith”, was fully evacuated after the explosion.

Superintendent Ian Pilling said: “This was a despicable offence. Children were in the process of leaving, nobody was killed or injured but that was down to good luck. Certainly from what I have seen anybody in the vicinity of the vehicle could have been injured or killed.

"This is an extremely unusual offence and I would like to reassure the public that it appears to be an isolated incident. We will do our utmost bring the offender to justice."

St Edward’s College is a voluntary aided faith school for boys and girls aged 11 to 18. It has around 1280 students including the brother of Colleen McLoughlin, who is engaged to Wayne Rooney.

The small bomb, which police suspect was an improvised device, exploded beneath a silver saloon belonging to a teacher. The interior of the car was extensively damaged and the windows were smashed.

Forensic teams are at the scene, carrying out a finger-tip search of the area. Police are studying CCTV footage taken outside the school and they are appealing for parents collecting their children, or members of the public who might have seen anything suspicious, to contact officers.

Damon Younis, 38, who lives next to the school, said: “There was a bomb, it was a nail bomb. I don’t think anyone was injured. The car was at the entrance to the school and one police car has arrived.”

Merseyside police were called to a school in West Derby after Merseyside Fire Service attended a report of a vehicle on fire. On arrival officers found that the car had been bombed.

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