The Russian Federal Security Service (FSB) said on Monday it detained a Ukrainian citizen for spying.

A man, whose name was withheld, was caught "red-handed while gathering classified information about research and development in small arms” production, the FSB said in a statement.

According to the FSB, "a foreigner on the instructions of the intelligence services of Ukraine was searching for employees of Russian defense enterprises having access to classified information."

-His goals were to recruit Russians and obtain from them legally protected information about promising developments in the field of small arms- it said.

A criminal case was opened against the Ukrainian on espionage charges, entailing imprisonment for a term from 10 to 20 years.

As of filing this report, Ukraine was yet to make an official statement about the arrest of its national.