Gunmen shot dead two British soldiers as they picked up pizzas at the entrance of an army base in Northern Ireland in an attack that appeared aimed at provoking a new round of violence in the province.
Political leaders in Britain and Ireland said the Saturday night attack must not derail the peace process.
It was one of the worst acts of violence in the province since the 1998 peace deal was signed to end decades of political and sectarian strife.
It followed a police warning last week that the threat from splinter groups from the Irish Republican Army was at its highest for nearly a decade and reports that British special forces were back in Northern Ireland to gather intelligence.
Four people, including two pizza delivery men, were also wounded in the attack, Irish public broadcaster RTE. The victims were taking delivery of a pizza at the Massereene base near the town of Antrim, 25 km northwest of Belfast, when gunmen pulled up in a vehicle and opened fire.