Prime minister David Cameron has been chairing an emergency meeting in Downing Street this morning as London - and other parts of the country - struggles to come to terms with the worst night of rioting in 20 years.

Police struggled to stop looting and disorder for a third night in succession, as the violence spread to Birmingham, Liverpool and Bristol.

The prime minister cut short his summer break and flew back from Italy overnight to deal with the crisis and led a meeting of the government's Cobra emergency committee this morning.

Speculation is growing that Parliament may be recalled later this week as calls for tougher measures to be used to stem the riots intensify.

Last night it emerged that specialist police officers from East Anglia were called into help maintain order on the streets of London as violence continues to erupt.

Trouble first flared on Saturday after a peaceful protest in Tottenham over the fatal shooting of a man by police.

The situation has continued to escalate with shops being looted and buildings set alight as police clashed with youths.

And with violence scenes continuing for a third consecutive day, officers from other parts of the country, including Suffolk, have been mobilised to help ease the situation.

A member of staff at Suffolk Police's control room confirmed that a Police Support Unit (PSU) which can contain between six and 18 officers, has been sent to London.

He indicated that more might be mobilised if the situation continues to worsen, but could only confirm that one unit had so far been sent.

Meanwhile a control room inspector at Norfolk police said no officers from Norfolk had been sent 'at this time'.

The prime minister is returning early from holiday to chair a meeting of the government's emergency committee Cobra.

David Cameron, who is on holiday in Italy, was due to board a flight on Monday night ahead of a meeting with Home Secretary Theresa May and Acting Metropolitan Police Commissioner Tim Godwin on Tuesday.

A government spokesman said the prime minister has been monitoring the situation on 'an hourly basis'.

Monday's violence started in Hackney after a man was stopped and searched by police but nothing was found.

There were also fears trouble may spread further afield as police in riot gear were deployed in Birmingham city centre after scores of youths rampaged through the shopping area, smashing windows and looting from shops.

Have you been affected by the UK riots? Have you had to cancel a business meeting or put off a trip to London or other parts of the country where rioting has taken place? If so call crime correspondent Peter Walsh on 01603 772436 or email peter.walsh@archant.co.uk

Have you got pictures or video of the riots? Email picdesk@archant.co.uk