Irish nationalist gangs hurled gasoline bombs at police after three alleged IRA dissidents were arrested on suspicion of killing two British soldiers in an attack designed to trigger wider violence in Northern Ireland. Police operating in armored cars and flame-retardant suits said none of their officers was injured during the rising mob violence on Saturday in the Irish Catholic end of Lurgan, a religiously divided town southwest of Belfast. Rioters also blocked the main Belfast-to-Dublin railway line that runs alongside the hardline Kilwilkie neighborhood of the town. Later, police said they arrested a 37-year-old man and 30-year-old woman, and seized a gun and ammunition in the neighboring town of Craigavon, where Irish Republican Army dissidents shot to death a policeman Monday. Police would not say whether those arrests and the arms find were connected to the March 7 shooting of the soldiers or the subsequent killing of the policeman. Police said the couple were being questioned about unspecified "serious terrorist crime."