Martin Jaager, an Estonian citizen who served in Ukraine's defense forces, was killed in combat in the Luhansk region, Estonian news outlet Postimees reported on June 23.
Jaager was killed on June 22 near the village of Raigorodka, close to the border of the Kharkiv and Luhansk Oblasts.
He was the third Estonian to die defending Ukraine, and was a member of the Third Assault Division.
A 42-year-old professional soldier, Jaager had been in an elite unit of the Estonian army for over a decade. He joined the defense forces in Ukraine over a year ago, and had served in various units before joining the Third Assault Division a month prior to his death.
In March 2023, Ivo Juurak was the first Estonian volunteer who was killed in action in Ukraine, followed by Tanel Kriggul in September. They were members of the International Legion, which Ukraine established in February 2022.