KYIV/MOSCOW/ST. PETERSBURG - Ukrainian President Volodymyr Zelensky on Friday signed legislation allowing certain convicts to join the country's armed forces, the parliament press service reported.

The legislation, which was adopted by the parliament on May 8, enables certain categories of convicts to be enlisted for military service under a contract during martial law.

In exchange, the convicts will be granted the possibility to get parole from serving their sentences.

The new law will not apply to prisoners who were convicted for crimes against Ukraine's national security, intentional murder of two or more persons, and other serious crimes

The new law will not apply to prisoners who were convicted for crimes against Ukraine's national security, intentional murder of two or more persons, and other serious crimes.

Last week, Justice Minister Denys Maliuska said that Ukraine has the potential to conscript between 10,000 and 20,000 convicts, according to media reports.

On May 18, a law to tighten military mobilization rules, which aims to recruit more troops for the country's armed forces, will take effect in Ukraine.

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Vow retaliation

On Friday, the Russian Foreign Ministry said the country will retaliate against Ukrainian attacks on its regions.

Russia will respond to such encroachments on its territory, the ministry's spokesperson Maria Zakharova was quoted by the ministry as saying. She added that Western involvement is clearly evident behind Kyiv's "attacks."

Maria Zakharova, spokesperson for the Russian Foreign Ministry, said the West is not only supplying Kyiv with longer-range missiles and heavy weaponry, but also clearly authorizing their use against Russia, thereby contributing to further escalation

Zakharova noted that the West is not only supplying Kyiv with longer-range missiles and heavy weaponry, but also clearly authorizing their use against Russia, thereby contributing to further escalation.

On the same day, the Ukrainian president was quoted by the Interfax-Ukraine news agency as saying that his country is no longer experiencing an artillery shell shortage.

Blast in St. Petersburg academy

Separately, seven soldiers were injured after a World War II-era munition exploded in the Military Academy of the Signal Corps in St. Petersburg on Friday, Russia's Leningrad Military District said.

The explosion occurred during the cleaning of one of the basement premises, when people unloaded garbage into a container, the district's press office said.

A 76-millimeter World War II-era munition "arbitrarily detonated," the press office said.

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The wounded have been taken to the Defense Ministry's health facility, according to the press office.

Governor of St. Petersburg Alexander Beglov has denied that the incident was terrorist-related.