Rioting which followed the Apprentice Boys parade in Derry last weekend was orchestrated and well planned, the High Court in Belfast was told yesterday.
"There was nothing impromptu about the violence on the streets and the police are concerned that there might be further violence in the city throughout the rest of the summer," said a prosecution lawyer.
He was opposing bail applications by three men and a youth arrested during a night of petrol-bomb attacks on police and property which caused damage estimated at £4 million sterling.
Mr Keith McCoy (17), of Iveagh Terrace, Derry, was spotted carrying a crate of bottles believed to be petrol bombs, the lawyer claimed.
"When police searched the immediate area they uncovered 15 milk crates and bottles in various stages of preparation and construction," he said.
The lawyer alleged that Mr McCoy, who was charged with making and possessing petrol bombs, confessed to having a crate of bottles in his possession and told police he intended to make petrol bombs with persons unknown to him.
Mr McCoy's lawyer said he had been asked to carry the crate and was merely a "porter".
Mr Charles McKnight (25), of Rinmore Drive, Derry, accused of throwing a petrol bomb at police, was alleged to have said he got "carried away" by the crowd.
A lawyer for Mr McKnight said he was a registered heroin addict and was "as high as a kite" when the incident happened.
Mr Paul O'Neill (23), of Barnailt Park, Claudy, near Derry, also charged with throwing a petrol bomb, was masked when he was spotted on a surveillance video, said the lawyer.
He said as police moved in Mr O'Neill discarded his mask but was identified and arrested. He admitted being in the crowd but denied throwing petrol bombs.
Mr Ryan McCradie (18), of Carnhill Estate, Derry, who was charged with possessing a petrol bomb, was alleged to have run at an armoured police vehicle with an unlit petrol bomb in his hand.
Mr Justice Higgins refused the bail applications.