A bomb was thrown into the reception of a hotel in Londonderry by a masked man, causing extensive damage.
A local MP is describing the incident, which happened at the Everglades Hotel in the Prehen area of Derry last night as an attack on the whole city.
It detonated a short time later as Army bomb disposal officers were urgently working to defuse it. No-one was injured in the explosion.
The finger of suspicion will be pointed at dissident republican extremists opposed to the peace process.
Foyle MP Mark Durkan said those responsible were trying to drag the city backwards.
"People of Derry won't see this as an attack against a particular site but, in fact, an attack against the
whole city," he said.
"So many people are working hard to move the city forward, but those behind this device are trying to drag us all back to worse times. Such methods demonstrate only a negative, violent capacity, not a viable strategy or credible rationale.
"The nature of the device, and the manner of this reckless attack, show that they are a threat to anyone and everyone. That is why we must be united and strong in rejecting their ways, and affirming peace and progress as our chosen determined collective right."
A Police Service of Northern Ireland (PSNI) spokeswoman praised "the swift actions of hotel staff and responding police officers in ensuring all guests were quickly evacuated".
"Their actions have undoubtedly helped to prevent a tragedy," she added.
Hotel guests have been transported to other hotels in the city. A road closure is in place around Victoria Road.
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