Northern Ireland Police have arrested two men in connection with the murder of journalist Lyra McKee.
Ms McKee was killed by a gunman shooting in the direction of police officers on Thursday (local time).
She died shortly after tweeting a photo of a police vehicle being pelted by petrol bombs, with the caption: "Derry tonight. Absolute madness".
The Police Service of Northern Ireland tweeted on Saturday morning that two men, aged 18 and 19, had been arrested under the Terrorism Act in connection with Ms McKee's murder.
Rioting hit the Irish nationalist Creggan area late on Thursday after a raid by police, who said they were trying to prevent militant attacks during the Easter weekend.
At least 50 petrol bombs were thrown and two cars were set on fire.
The attack, which shocked the region, was likely the work of Irish nationalist militants opposed to the 1998 Good Friday peace deal, police said.
