MOSCOW, May 27 (Reuters) - The death toll from a bomb blast in the southern Russian city of Stavropol rose to seven on Thursday and 16 people were in a critical condition, Russian media reported.
The blast occurred on Wednesday just before the start of a concert by a dance company linked with Kremlin-backed Chechen President Ramzan Kadyrov.
Russia said investigators had opened a criminal case under terrorism laws after the blast in the ethnically Russian Stavropol region, which borders the violence-racked, mainly Muslim republics of the North Caucasus.
Islamist militants have vowed to expand a campaign of shootings and bombings to Russian cities. Suicide bombers on the Moscow metro in March killed 40 people in the worst attack on the Russian heartland since 2004.
A Stavropol doctor told Rossiya-24 television that the death toll had risen by two ovenight to seven and that 16 people were in an "extremely grave condition" with chest, abdominal and head wounds.
The bomb, equivalent to 400 grams of TNT, was disguised as a pack of juice.
Last year, Russian President Dmitry Medvedev ordered that the Stavropol region be included in a new North Caucasus Federal District along with mainly Muslim Chechnya, Dagestan and Ingushetia in a bid to tackle growing violence. (Reporting by Dmitry Solovyov; Editing by Ralph Gowling)
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