The former commander of the Russian mercenary group Wagner, who recently fled to Norway, has been detained by the police, an official said on Monday.
"He is detained ... and we are considering whether to seek a court order for detention," police lawyer Lyne Isaksen said, declining to give details.
Prisoners' rights group Gulagu.net published on Monday a recording of a telephone interview with Andriy Medvedev, in which he urged Norway to allow him to stay and testify against Wagner.
Medvedev was arrested on Sunday, handcuffed at the hotel where he was staying, and taken to a pre-trial detention center. Gulagu.net reported that Medvedev was told he was at risk of deportation.
Medvedev's Norwegian lawyer Brynulf Risnes told Reuters: "The risk of his deportation is zero."
According to Risnes, the police detained Medvedev because there were "disagreements" between them about the measures taken to ensure his safety.
"He's under very tight security measures and we don't agree with how they're being applied. It's caused friction," he said.