Police came under sustained attack in east Belfast last night during a second night of violent clashes.

Blast bombs, petrol bombs and other missiles were thrown at officers who were in the area monitoring the volatile situation.

Missiles were also thrown between loyalist and republican mobs gathered at the flashpoint on the lower Newtownards Road.

Several hundred people were in the area watching as youths wearing masks battered police Land Rovers with sledgehammers and bricks. At one stage a rioter almost got into the back of one of the armoured vehicles while others jumped on top of them.

Tensions were running high on both sides throughout the evening. Violence eventually flared shortly after 9pm with both sides claiming the other was responsible for starting the outbreak of disorder.

On Monday night UVF gunmen opened fire on PSNI officers as the police tried to control hundreds of rioters in the same area in what is feared to be a sinister prelude to a summer of sectarian trouble.

The PSNI is treating those attacks, carried out during almost five hours of sustained disorder, as attempted murder.

Police fired plastic bullets after the warring factions shot at each other with live rounds.

At least two shots were fired at officers by members of the UVF. A total of 11 shots were fired from both republican and loyalist areas.

Petrol bombs and blast bombs were also thrown during the clashes, which the PSNI believes began when a loyalist gang invaded the republican Short Strand area, causing damage to a number of homes.

A group of republicans retaliated and within minutes up to 500 people were on the streets rioting.

"This was high level, life-threatening, organised, serious and sustained public disorder," said Chief Superintendent Alan McCrum.

Mr McCrum said it is the PSNI's belief that the east Belfast UVF orchestrated the trouble. He added that investigations are continuing into whether the violence was sanctioned by the UVF leadership - once again raising questions over the loyalist terror group's ceasefire status.

Mr McCrum said yesterday the PSNI would do all it could to stem the tide of violence. "All available resources will be brought to bear to ensure we do not have a repetition of the disorder," he said.

He added that officers acted bravely in a challenging set of circumstances.

"Within a very short space of time we had hundreds out on the streets. The police officers were outnumbered and I think we did a very good job trying to manage what was a very difficult and challenging public order situation," he said.

"No-one could have anticipated the scale of the disorder that took place. No-one could have anticipated that hundreds of people would be on the street and that petrol bombs, blast bombs, sticks and bottles would be thrown for four to five hours."

CCTV footage gathered by police is being analysed by a public order inquiry team in a bid to identify those involved in the violence.