A security alert in Derry's Bogside has now ended, however police remain at the scene carrying out further examination.
Police say a number of viable devices found at a property in Maureen Avenue, a residential area, have been made safe by ATO and have been taken away for further forensic examination. A number of residents remain out of their homes.
A 30 year old man arrested on suspicion of dissident republican activity remains in custody helping police with their enquiries.
Foyle Area Commander Chief Inspector Garry Eaton said the devices were found in a flat, in the middle of a built up residential area whch could have caused significant damage or serious harm to local people.
He acknowledged that evacuating the area casued disruption, but said the PSNI's primary concern was to keep people safe.