MOSCOW, November 6. /TASS/. Serious crimes like the shelling of a school in Donetsk, in eastern Ukraine, must not remain unpunished, the speaker of Russia’s lower house of parliament, the State Duma, said on Thursday.

“Yesterday Donetsk again was shelled by armed groupings, subordinated to the official Kiev. The school became one of the targets in this shelling which killed two teenagers as a result,” Sergey Naryshkin said.

“Such crimes must not be unpunished,” Naryshkin stressed.

Earlier on Thursday, Russia’s Investigative Committee opened a criminal case into the shelling of the Donetsk school.

According to investigators, on Wednesday afternoon servicemen of Ukraine’s Armed Forces and National Guard launched artillery shelling upon instructions of their commanders directly targeting school number 63 in Donetsk.

Two teenagers were killed in the shelling while playing on the school sports field. Three other locals, reportedly aged between 17 and 21, sustained various injuries and have been hospitalized.

Investigators suspect that the attack was launched to “eliminate a Russian-speaking ethnic group living on the territory of the self-proclaimed Donetsk People’s Republic,” spokesman Vladimir Markin said.

The shelling comes in violation of international conventions, including the United Nations Convention on the Rights of the Child and also the protocol on ceasefire in south-eastern Ukraine and a memorandum signed in the Belarusian capital Minsk in September.