MOSCOW (AP) — Moldova’s breakaway region of Transnistria, which has close ties to Moscow and hosts Russian troops, claimed Thursday it has thwarted an assassination attempt on its president allegedly organized by Ukraine’s national security service.

Transnistria’s state security ministry said an unspecified number of people had been arrested in connection with an attempted attack on the region’s president, Vadim Krasnoselsky, and other officials.

Prosecutor Anatoly Guretsky said the suspects planned to detonate an explosives-packed automobile near the presidential cortege as it traveled through the capital, Tiraspol.

It said Ukraine’s SBU security service ordered the assassination attempt, but did not provide evidence.

The SBU rejected the allegation, saying it “should be considered exclusively as a provocation orchestrated by the Kremlin.”

A separatist war broke out in 1990 in Transnistria — a strip of land with about 470,000 residents that borders Ukraine. As part of a cease-fire in 1992, a contingent of Russian troops remains there as nominal peacekeepers.

Since Russia sent troops into Ukraine more than a year ago, concerns have been high that Moscow would try to take control of Transnistria.

But Russia’s Defense Ministry has claimed in recent weeks that Ukraine has designs on Transnistria, either through mounting a “false-flag” attack that could be blamed on Russia or by sending in its own troops.

Moldova’s pro-Western government said it was following developments but could not confirm the attempted assassination claim.