MOSCOW — A homemade bomb went off in a school attached to an Orthodox Christian convent and wounded 12 people, while an 18-year-old former student was identified as a suspect in the explosion, Russian authorities said Monday.

The bomb detonated at the Vladychny convent in Serpukhov, a city 65.2 miles outside of Moscow, the Russian Interior Ministry said.

Authorities said the teenager suspected of planting the bomb survived and was in intensive care. Media reports suggested he may have been motivated by hatred of teachers and nuns at the school.

Staff and students were evacuated from the scene. Russia’s Investigative Committee opened an investigation.

Patriarch Kirill, the head of the Russian Orthodox Church, urged support for those wounded in the explosion and said he hoped authorities would do everything necessary to prevent such an incident from happening again.