A police officer from Walthamstow who kicked a 15-year-old boy in custody days after the London riots has been cleared of assault.

PC Joseph Harrington, 29, was accused of using unreasonable force to restrain the youth at Forest Gate police station back in August 2011.

The court heard he had worked 100 hours in the previous five days and had left the teenager "crying, coughing and spluttering" after allegedly stamping on his back following his arrest earlier in the day.

But PC Harrington denied the claims and said he had "stuck to his training" by pinning the boy down with his knee as he tried to reposition his handcuffs.

He admitted kicking the youth on the back of the legs but said this was a standard police technique and said the 15-year-old was being aggressive and abusive.

A jury took just 28 minutes of deliberations to unanimously clear PC Harrington, who lives in Chaucer Road.

The court heard that the boy, who cannot be named for legal reasons, had never previously been in trouble with the police at the time of the incident on August 11.

But since then he has been convicted of six offences, including obstructing powers of search, damaging property, possession of cannabis, and one count of battery committed while on bail.

Prosecutor Duncan Atkinson said PC Harrington had been very tired and had lashed out.

He said: "Those who saw it considered that there was no justification for what the defendant did and the prosecution case is that there was neither justification nor lawful excuse for this officer's treatment of a young, handcuffed man, in his custody."

It was claimed that the incident took place days after a previous alleged confrontation when the youth claimed PC Harrington had put his hands round his neck.

The officer denied having contact with the teenager then but said he recognised him from several months earlier.

He said he knew from police intelligence that the boy was an "active street robber and gang member" who was known to be violent towards police.

PC Harrington told the court the boy had become aggressive and started "'jabbing his arms towards me…and shouting d****head."

He added: "I dropped my knee using some force, but it was a controlled dropped.

"I did not stamp on him at all. As soon as he said 'I can't breathe' I took my knee off."