The Ukrainian State Border Guard Service has confirmed that a Russian serviceman who was heading to Transdniestria was detained on the Ukrainian border over a month ago.

"The situation took place back in early June," Ukrainian State Border Guard Service spokesman Oleh Slobodian said.

"Valery Georhiyovich Voitenko, born in 1954, a citizen of Ukraine, came to a Ukrainian border-crossing checkpoint at about midnight and produced a Ukrainian passport. A senior border guard officer of the second control line doubted the purpose of this person's visit (he produced a telegram from Transdniestria stating that his mother is seriously ill and gave confusive information about data in his passport)," Slobodian said on Facebook on Sunday night.

Officers of the State Border Guard Service's operative units came to the checkpoint for detailed questioning of the suspicious person.

The man was asked to produce the content of his pockets and luggage. He produced a cell phone, which contained photos of rallies held in Donetsk and Luhansk, money and bus tickets.

"A detailed examination of the suspect's belongings revealed a secret pocket in the suspect's jacket. A piece of paper with background information and telephone numbers of Transdniestrian senior officials and people from Russia, the Order of the Red Star, a smart phone and flash cards were taken from the secret pocket," Slobodian said.

The photo and video materials from the smart phone prove that the detainee had earlier visited the DPR and the LPR, where he met with the command of DPR and LPR armed units, he said.

The border guards had identified the man, Slobodian said. "The man is Valery Gratov, a colonel of the Russian Armed Forces, born in 1952, whom the Russian special services planned to make 'deputy' state security minister of Transdniestria," he said.

The detainee was handed over to officials of the Ukrainian Security Service, Slobodian said.