Hunt on for thrower of fire extinguisher

London: A man was arrested and then released on police bail in Cambridgeshire on Friday by officers hunting for the protester who threw a fire extinguisher from a roof at Wednesday's anti-tuition fees demonstration.

The fire extinguisher was thrown after protesters swarmed into Millbank Tower, the Westminster building that houses the Conservative party's headquarters. The incident, which police say could have led to the death of an officer, was caught on video.

The man, 23, understood to be from Reading and studying at Anglia Ruskin University, Cambridge, was arrested by Cambridgeshire police at the request of the Metropolitan police. He was held at Parkside police station in Cambridge, the police said.

Paul McKeever, the chairman of the Police Federation, said that whoever threw the fire extinguisher should be charged with attempted murder.

Police said 10 of the 56 people arrested during the protests were under 18.