Late last night police in Londonderry received a call. A bomb was about to go off. They had an hour to clear the area. They did, moving everyone away, including residents of a home for the elderly. No one was hurt when the bomb went off, though there was considerable property damage.
The BBC is reporting that the violence is being widely condemned at the national and local level.
Mayor of Derry Colum Eastwood was at the scene when the device exploded.
"I saw the bomb go off. We were not far away," he said.
"It is just shocking that someone would put a bomb anywhere, but especially at a commercial centre.
"I do not know what these people are hoping to achieve. They say they love their country but they spend their time trying to destroy it. The people of this city will be very angry."
Police blame Irish dissidents who want to derail the peace process. There have been a number of attacks in recent months, and last week British officials warned of the potential for further strikes, saying they were concerned about possible bombings on mainland Britain.