A man has been arrested on Wearside over a bomb alert which prompted the evacuation of a police station.
Two suspect packages were handed to officers in Sunderland on Tuesday which led to the evacuation of the city's main police station.
They were later declared safe by army bomb disposal experts from Catterick.
A Northumbria Police spokeswoman said a 20-year-old local man had been arrested on suspicion of having explosives in suspicious circumstances.
The packages, inside two bags, were found by council contractors in bushes near the city's Chester Road.
An incident room remains in operation and house-house inquiries into the incident are continuing.
CCTV footage from city cameras is also being examined.
Further searches of waste ground where the packages were found unearthed no further items.
The packages were still being examined by forensic experts and the force spokeswoman said it would be "some time" before a full analysis was complete.