Asian taxi drivers are calling on police to do more to protect them from racist attacks.

The news comes after the Crown Prosecution Service revealed the number of defendants prosecuted for racially aggravated offences in the Thames Valley doubled in a year. The figure rose from 88 defendants in 2004/05 to 177 in 2005/06.

The CPS could not break the figures down to show how many racist offenders were from Oxfordshire. Oxford city councillor Sajjad Malik, who drives a black cab, called for the police to work harder to catch those responisible for racial crimes against taxi drivers, and for courts to be tougher on them.

He said: "There was a meeting about this at the town hall and I spoke to some of the cabbies. They are not very happy. If cabbies report this and nothing happens they just get on with it. Sometimes they don't go to police even if there has been criminal damage to their car."

"One cabbie was attacked and his car driven into a shop on High Street. The offender got off lightly because the CPS did not bring the right charges. In another example, someone grabbed a cabbie by his neck. The cabbie rang 999 and said someone was going to strangle him.

"He told police the offender had got out of the car and they said it was not an emergency because he was no longer trying to strangle him.

"The driver was left shaken, distressed and upset. I was assaulted in July in St Giles. The offenders kicked my cab and racially abused me.

"As I got out they assaulted me. My elbow and knees were bruised because I fell on the floor.

"The police just said they couldn't trace the offenders. Cabbies are eyes and ears for the police, the service we provide is vital to them.

"Whatever the system is, we feel let down by it. We want a more common sense approach."

Chief Crown Prosecutor Baljit Ubhey said CPS Thames Valley was working with Asian taxi drivers, the police and local authorities about the under reporting of racially aggravated assaults.

Miss Ubhey said: "Racially aggravated crimes are among the worst sort of crimes in our society because they don't just affect individual victims but whole communities.

"The CPS is determined that we will take a robust view of these cases and that prosecutors will work closely with the police to make sure the strongest evidence is put before the courts to convict offenders.

"I take a particular interest in racially aggravated offences and push forward local initiatives to raise awareness and increase confidence in the criminal justice system."