Detectives investigating the murder of Lyra McKee in Creggan on Thursday, April 18, confirmed they conducted two searches in Derry on Wednesday, August 7.
A 34 year old man was also arrested in relation to a separate investigation into the attempted murder of police at the City Walls on July 11, 2018.
He has been taken to Musgrave Street Serious Crime Suite where he is currently being questioned by detectives.
Earlier, the hardline republican party Saoradh claimed two of its members were detained in raids on their homes in Derry this morning.
In a statement the group said: "The Revolutionary Republican Party, Saoradh, have been targeted by British Crown Forces again today as currently two party members have been detained following early morning raids on their family homes."
The PSNI operations took place in the Bogside and Ballymagroarty.
Saoradh said one member was detained while the other member was "held for the duration of the raid but not taken to Musgrave".