Russian President Vladimir Putin speaks at a celebration to mark the first anniversary of Crimea's incorporation into Russia, in Moscow, Russia, March 18, 2015. (Xinhua Photo)

MOSCOW, Feb. 12 (Xinhua) -- The Russian Federal Security Service (FSB) said Monday that it has detained a Ukrainian citizen suspected of conducting espionage in Crimea.

The detainee, identified as Konstantin Davydenko, is suspected of "purposefully collecting and transmitting to the special services of Ukraine information on the activities of units of the Russian National Guard and employees of the FSB, and the leak could damage the security of the state," an FSB statement said.

The FSB has initiated criminal proceedings against the detainee for espionage, and an investigation is underway, it said.

Crimea, formerly part of Ukraine, was absorbed into Russia in March 2014 following a local referendum, which was rejected by Ukraine and its allies.

Since then, the FSB has published several reports on the detention of suspected Ukrainian spies or saboteurs in Crimea, but Ukraine has consistently denied such acts.