The Croatian Foreign Ministry said on Saturday that a Croatian national was taken prisoner in Ukraine and that it was working on solving the case in cooperation with the Ukrainian authorities.

The ministry said that due to the delicate situation, it could not divulge more details at the moment.

Russian media said a “Croatian mercenary” was taken prisoner in Mariupol.

N1 television reported that a Croatian national told Russian RT television that he had been a soldier in a Ukrainian marine brigade which was hiding in Mariupol and that the Russians took him and several other fighters prisoner as they attempted to flee the city under siege.

RT showed a photo in which he is sitting in a room at an unknown location.

“We were leaving Mariupol, walking 260 kilometres by night, hiding, avoiding every possible contact. But our plan failed when we ran into a Russian artillery unit. We had to surrender,” he said, according to N1.

According to the Russian portal pikabu, the Croatian national said he had heard that Ukrainian paramilitaries did “terrible things to civilians, to prisoners” and that among them were “many criminals, drug addicts.”

“They probably even shot at us sometimes,” he told the portal.