ANTANANARIVO, Madagascar (AP) — Police in Madagascar say two protesters were killed in a riot at a prison holding the alleged killers of a French nun. The government is investigating reports that security forces fired on the crowd.

Police Lt. Col. Lala Rakotonirina said Tuesday that the unrest happened when a crowd, angry at the death Sister Marie Emmanuelle Helesbeux, converged on the prison in the northern town of Mandritsara.

Authorities say one of the three suspects owed money to Helesbeux, who was strangled. Her body was found Saturday in the Mandritsara marketplace.

Interior Minister Florent Rakotoarisoa and other government officials traveled to Mandritsara. The interior minister said on national radio that "popular justice" and revenge will not bring peace to the town, and that the suspects will be harshly punished if found guilty.