A Ukrainian military official who blew himself up with a grenade he got as a gift probably 'did not believe' it was real

A Ukrainian military aide who blew himself up with a grenade he was given as a birthday gift probably didn't believe it was real, according to a preliminary investigation.

Hennadii Chastiakov, the assistant to Ukraine's commander in chief, Valerii Zaluzhnyi, was celebrating his birthday on Monday when a grenade went off, Ukraine's interior minister, Igor Klymenko, said in a Telegram post on Monday.

Chastiakov died in the explosion, and his 13-year-old son was taken to the hospital with serious injuries, according to reports.

The grenade had been in one of his birthday gifts, according to reports, and a preliminary investigation revealed the explosion was likely an "accident," Maryana Reva, a spokesperson for Ukraine's Ministry of Internal Affairs, told Radio Svoboda.

Reva said that the man who most likely gave Chastiakov the grenades had turned himself in.

The suspect had "warned that the grenades were live ammunition," Reva told the outlet, but "the deceased probably did not believe this information," she said.

Ukraine's National Police found five unexploded, Western-made grenades at the scene and searched the suspect's office, where they seized two similar grenades, Interior Minister Klymenko said.

He added that preliminary results suggested that Chastiakov had turned the ring of a grenade, causing it to explode.

Chastiakov's wife said her husband had brought home a gift bag containing a bottle of alcohol and shot glasses in the form of grenades, Ukrainska Pravda reported, citing law enforcement agencies.

When he opened the package, it blew up, according to the report.

According to the Guardian, Chastiakov's death was initially viewed as a suspected assassination.

However, that's no longer the case.

The accident caused "unspeakable pain" and is a "heavy loss" to the military, Zaluzhnyi said in a Telegram post on Monday.

He added that Chastiakov had been a "reliable shoulder" to him and had been "completely devoting his life to the Armed Forces of Ukraine and the fight against Russian aggression," according to a translation by Politico Europe.