A fire at the Sammy Duddy conflict transformation centre building on York Road was reported at 1.30 am this morning, Sunday, July 12.
A number of windows had been smashed and three petrol bombs had been thrown in.
Police said two of the petrol bombs ignited causing slight scorch damage to a ground floor office.
An unexploded pipe bomb was also discovered at the scene.
Army Technical Officers attended and made it safe before it taken away for forensic examination.
Detective Sergeant Michael Hawthorne said: “I appeal to anyone who has information in relation to this incident to contact detectives at Musgrave on the non-emergency number 101 or alternatively contact crime stoppers on 0800 555 111.”