The Ministry of Foreign Affairs of Ukraine has demanded Russia provide reasons for the detention of Kharkiv resident Oleksandr Steshenko, the Foreign Ministry's press secretary, Maryana Betsa, has said.

"As regards the detention of Oleksandr Steshenko at the entrance to the occupied Crimea, we've sent a note to the Russian Federation with a demand to state the reasons for the detention and his location," Betsa wrote on Twitter.

Earlier, the Crimea.SOS project reported that on April 1, Russian law-enforcers detained Steshenko at the Chonhar checkpoint at the entrance to the annexed Crimea. That day, he called his mother and said that the Russian law-enforcers in Chonhar said they had doubts about his resemblance to the photo in his passport.

According to activists, on April 14, the frontier guards of the Russia Federal Security Bureau first confirmed that they held Steshenko, but then refused to let him speak with a lawyer, and then denied this information.

At present, the whereabouts of Steshenko is unknown.