Police in Derry have named a 19-year-old man who was found dead in suspicious circumstances in a flat in the city on Friday.
Gerald Martin O Hagan was discovered in the Galliagh area of the city, shortly after 12.30pm.
The PSNI confirmed a man had been arrested in connection with the incident and was helping officers with their inquiries.
A police spokesman appealed for anyone who witnessed any suspicious activity in Galliagh Park to contact them.