VILNIUS, Lithuania (AP) — Lithuanian authorities say they have foiled an international plot to kill an activist who has supported Ukraine in its fight against Russia and an exiled Russian citizen who has favored independence for his home region.

The prosecutor general’s office on Monday said 13 suspects from Belarus, Georgia, Greece, Latvia, Moldova and Russia were involved in the plot involving “preparation to murder two people for terrorist purposes.”

Nine suspects have been arrested in Lithuania and abroad, and the whereabouts of the other four are known by Lithuanian authorities, officials said.

They allegedly worked together to scout out the activists’ homes and workplaces and share advice on acquiring a weapon.

Prosecutors identified the targets as Valdas Bartkevičius and Ruslan Gabbasov.

An investigation was opened when Gabbasov contacted authorities early last year after he discovered a tracking device left on his car by an unidentified person. Weeks later, most of the suspects were detained by an anti-terrorism unit, officials said.

Bartkevičius told The Associated Press he believes he was targeted for his activism supporting Ukraine, for entering parts of Russia’s Kursk region while it was under control of Ukrainian forces and for urinating on a war memorial there.

Gabbasov, who hails from Russia’s Bashkortostan region, says he believes he was targeted because he calls for the region’s independence. He has received political refugee status in Lithuania and is wanted by Russian authorities.