A bomb exploded close to a busy restaurant in Belfast on Friday night as police were clearing people from the area, leaving no one hurt, the Police Service of Northern Ireland said.
The explosion took place just before 7pm (1900 GMT) in the city’s Cathedral Quarter which was thronged with Christmas shoppers and people enjoying an evening out.
Police said the device “could have killed or maimed anyone nearby” and about 1,000 people were affected by the evacuation and cordoning off of the area.
Police gave no immediate indication of who could have been behind the attack.
Northern Ireland endured decades of so-called “Troubles” when armed groups seeking unification with the Republic of Ireland and rival groups determined to keep Northern Ireland within the United Kingdom both waged violent campaigns.
The Troubles largely came to an end with the Good Friday Agreement signed in 1998, but Northern Ireland is still plagued by occasional outbreaks of sectarian unrest and by attacks by small dissident groups who have not accepted the peace deal.
A warning had been given in a telephone call to a newspaper but the unknown caller said the device had been left at a hotel when it was actually left on the footpath adjacent to the front of a busy restaurant, police said.
“This was an attack on the people of Belfast going about their normal lives on a busy night for socialising in the city. This attack ruined the night out for these people,” Chief Superintendent Alan McCrum said in a statement.
“Those who carried out this attack have nothing to offer except disruption and destruction.”
In London, Northern Ireland Secretary Theresa Villiers called the attack “deplorable” and said a small minority that wanted to drain the economic life from Belfast would not succeed.
“On one of the busiest nights of the year with people enjoying the festivities ahead of Christmas, as well as those in the final stages of Christmas shopping, it shows that these terrorists are stooping to a new low,” she said in a statement.