A nail bomb exploded today inside a car belonging to a teacher at a leading Liverpool school, police said.
The explosion, shortly before 3pm, seriously damaged the vehicle parked outside St Edward's College, a private Catholic school in West Derby. No one was injured in the blast.
Speaking outside the school, Superintendent Ian Pilling from Merseyside Police said the explosion appeared to have been timed to coincide with the end of the school day.
The car was about 10 metres from the school building when the device, inside the vehicle, exploded, Mr Pilling said.
"An explosive device had been placed inside the car," he said.
"At this stage we can't say exactly what device it was but it was detonated inside the vehicle.
"This was a despicable offence. Children were in the process of leaving. Nobody was killed or injured but that was down to good luck."
There was no damage other than to the car, another officer, Inspector Michael O'Callaghan, said, describing the device as a nail bomb.
Roads around the school grounds, which is a few miles outside Liverpool city centre, were cordoned off by police. The school was evacuated immediately after the device went off.
Map highlighting location of Liverpool, England.
A nail bomb has exploded under a car, thought to belong to a teacher, at least ten meters from the entrance of St. Edward's College in Liverpool, England at approximately 14.50 BST. There were no injuries, but the car was severely damaged in the blast.

Merseyside Police confirmed that officers were investigating a security alert at the college which is an independent Catholic boys and girls school for children ages 11-18.  They also confirmed that it was "some kind of explosive device" which was involved.

"There was an explosion under a car at the school this afternoon. What caused the explosion and the reasons behind it we are investigating. Nobody has been injured and there has been no collateral damage," said Michael O'Callaghan, an Inspector for the Scotland Yard. Other reports say that the bomb was inside the car.

Police believe that the bomb was timed to detonate at the time children were being let out of school for the day. Almost 2,000 students attend the school, which was evacuated after the blast.