Ukraine police are in a standoff with opposition activists at a Kiev hospital where a protest leader who says he was kidnapped and tortured is being treated.
Dmytro Bulatov went missing for eight days and is being treated in hospital after claiming he had been "crucified" by his captors.
Medical workers have blocked police from questioning Mr Bulatov, who is on a government wanted list.
He was found bloodied and bedraggled on the outskirts of the Ukrainian capital on Thursday and said he had been left to die by his captors.
"They crucified me, so there are holes in my hands now," he said. "They cut off my ear, cut up my face. My whole body is a mess."
The activist reportedly said he did not know who had abducted him, but his abductors had spoken with Russian accents.
The BBC reports that Mr Bulatov is the latest of a number of activists to have gone missing. At least one was later found dead.
The police said they had opened an inquiry into his abduction and were trying to question him about that. However opposition leader Vitali Klitschko, who was at the hospital, said about 15 officers had turned up with a court order to serve on Mr Bulatov that would allow him to be taken into custody.
One interior ministry official said there were suspicions the abduction was faked as part of an attempt at provoking unrest.
Protests broke out in November, when President Viktor Yanukovych pulled out of a deal with the EU in favour of a Russian bailout.
In mid-January, police and demonstrators clashed after the government passed a law severely restricting protesters' rights.
Mr Yanukovych has since ordered the law repealed, signed an amnesty for protesters and accepted the resignation of his cabinet.