BUCHAREST (Reuters) - Romanian prosecutors said on Friday they have opened a criminal investigation against a Romanian citizen accused of treason and spying for Russia for more than two years.

The country's anti-organised crime prosecuting unit DIICOT said in a statement the suspect surveilled Romanian or NATO military objectives near the southeastern Romanian county of Tulcea - near the country's border with Ukraine - beginning in 2022.

The suspect "collected military information and took photographs of military equipment and staff movements in the border area with Ukraine which he then sent to diplomats from the Russian embassy in Bucharest," the statement said.

Prosecutors added a Romanian court has approved the suspect's arrest for 30 days pending the criminal investigation.

The arrest is a first in Romania, a hub of Western military and humanitarian supplies to Ukraine since Russia's full scale invasion of the country.

The Russian embassy in Bucharest did not immediately respond to an emailed request for comment.

Romania, a NATO member since 2004, shares a 650-km (400-mile) border with Ukraine and has had Russian drone fragments stray into its territory repeatedly as Moscow attacks Ukrainian ports just across the Danube River from Romania.

(Reporting by Luiza Ilie; Editing by Kim Coghill)