(CNN) A gunman killed himself after shooting six people dead and injuring three others at a hospital in the eastern Czech city of Ostrava on Tuesday.

One of the victims was shot in an operating theater and later died. The head of the hospital, Jiří Havrlant, told reporters outside the hospital that all of the victims were patients, and that the suspect was shooting people at close range in their heads and chests.

The incident happened just after 7 a.m., according to interior minister Jan Hamáček, who added that police and emergency response units were in attendance.

Staff hide behind police vehicles near the hospital in the eastern Czech city.

Police said the "dangerous armed perpetrator" who was carrying a "short handgun" had fled the scene in a silver-gray Renault Laguna.

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