Rostov-on-Don, Russia ? A suicide bomber rammed a truck packed with explosives Friday into a military hospital near Chechnya caring for dozens of Russian troops. Officials said at least 27 people were killed with 15 others feared trapped in the rubble.

The four-story red brick hospital in the city of Mozdok was destroyed in the explosion, the latest in an upsurge of suicide bombings that have killed more than 100 people since May.

Russian authorities suspected Chechnya’s separatist rebels in the attack in the city of Mozdok in Russia’s North Ossetia region.

There were conflicting reports on the death count. Regional Emergency Situations Minister Boris Dzgoyev said at least 27 people were killed and 15 others feared trapped in the ruins. Russian Deputy Prosecutor General Sergei Fridinsky said 35 were killed. Another official put the toll at 33.

Dzgoyev said 76 people were injured, many of them soldiers who had been recovering from wounds suffered in Chechnya, where Russia’s second war against rebels in a decade has lasted nearly four years.