A Ukrainian official announced that Maj. Gen. Oleg Mityaev, a Russian military leader, was killed in battle on Tuesday.

Ukrainian Interior Ministry adviser Anton Gerashchenko said Mityaev was slain during an offensive on Mariupol. Gerashchenko shared a photo of what he said was Mityaev’s corpse on social media.

Ukrainian President Volodymyr Zelensky said on Tuesday night that a Russian general had been killed, but didn’t provide a name.

Russia has not confirmed the death, but if true, Mityaev would be the fourth Russian general to die in the invasion of Ukraine.

The 46 year-old Mityaev was the commander of the 150th motorized rifle division. He had fought in Syria and commanded troops in Tajikistan. Newsweek reports that he was one of 20 Russian generals deployed in Ukraine.

The outlet adds:

In only one week in early March, Ukraine reported the deaths of Major General Andrei Sukhovetsky, commanding general of the Russian 7th Airborne Division and deputy commander of the 41st Army, and Major General Vitaly Gerasimov, chief of staff of the 41st Army.

Sukhovetsky was killed by sniper fire, while Gerasimov was shot dead outside the eastern city of Kharkiv, according to Ukrainian reports. The death of Sukhovetsky was confirmed in a speech by Russian President Vladimir Putin on March 3.

Major General Andrei Kolesnikov, commander of the 29th Combined Arms Army, was killed on March 11, Ukraine said.

U.S. estimates put the number of Russian soldiers killed in Ukraine since the invasion began at between 5,000 and 6,000. Ukrainian armed forces say over 13,800 Russian troops have been killed since the beginning of the war on February 24, as reported by The Kyiv Independent.