Police officers in Belfast were pelted with fireworks and bricks in the Carlisle Circus area in the north of the city tonight.
Terry Spence, chairman of the Northern Ireland Police Federation, which represents rank and file officers, said: "Their bravery and courage is in stark contrast to that of the cowardly thugs responsible for trying to murder them."
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The Police Federation chairman said officers were often "letting someone off with a warning and hoping for the best".
A total of 21 are also injured by a blaze which ripped through the upmarket 22-storey hotel on the Black Sea coast.