London , England ( CNN ) -- The attackers who planted a car bomb outside a courthouse in Northern Ireland Monday night gave only 17 minutes warning before the explosion , the Police Service of Northern Ireland told CNN Tuesday . `` It is a miracle that no one was killed or seriously injured , '' PSNI Chief Constable Matt Baggott said . `` It is only thanks to a member of the public contacting us that we are not dealing with fatalities this morning . '' The car was packed with about 250 pounds ( 113 kilograms ) of explosives , police estimate . A local hospital in the town of Newry got a warning call at 10:20 p.m. local time ( 7:20 p.m . ET ) and a business was phoned two minutes later . The bomb went off at 10:37 p.m. , a police representative said . That `` is not enough time to evacuate a public area , '' a police representative said . British police spokesmen traditionally do not identify themselves by name . A member of the public reported a car being abandoned at about 10 p.m. , she said . That appears to have given police extra time to respond . Baggott blamed the attack on `` dissident republicans , '' pro-Irish militants who reject the 1998 Good Friday Agreement that sharply reduced violence in the province . They `` simply want to drag Northern Ireland back to the dark days of the past , '' Baggott said , condemning `` cowardly attacks '' by `` terrorists '' who `` want to destroy all that is good about Northern Ireland and have no place in a modern civilized society . '' `` This is not an attack on a court building , this is an attack on people whose lives depend on the well-being of Newry , '' he added . `` This is an attack that broke and damaged places of worship ... damaged the ability of Newry to be at the heart of our economic success . '' Newry is about 35 miles ( 56 kilometers ) south of the provincial capital , Belfast . Prime Minister Gordon Brown 's office `` strongly condemned '' the bombing , saying Tuesday it was the work of a `` tiny minority . '' The `` attack '' is `` entirely unrepresentative of the views of the vast majority of people in Northern Ireland , '' said a statement from Brown 's Downing Street office . The court building was badly damaged and businesses in the area were evacuated , police said . Northern Ireland was wracked for decades by violence between pro-British unionists and pro-Irish republicans . About 3,000 people died in the `` Troubles , '' as the violence was known , before the tenuous peace agreement was hammered out in 1998 . There has been sporadic violence since then . A booby-trapped car exploded on January 8 , severely injuring Constable Peadar Heffron . A car bomb partly exploded outside the headquarters of the Policing Board of Northern Ireland on November 21 , and another under-car booby trap exploded on October 22 in east Belfast , injuring a woman , the PSNI said . Two soldiers and a policeman were shot dead in separate attacks in March 2009 . The two biggest parties in the province , the pro-British Democratic Unionist Party and the pro-Irish Sinn Fein , reached a deal earlier this month to bring police powers under local control , averting a crisis that had threatened to force new elections .
Man who planted bomb in N. Ireland gave only 17 minutes warning before explosion . British PM Gordon Brown condemned car bomb outside court in Newry . No one was killed or injured in the blast . About 100 people died in case of violence before 1998 peace agreement .