The incident occured when the Telangana State Road Transport Corporation bus was proceeding to Karimnagar from Warangal, at about 9 AM, they said.
When the vehicle reached Chengerla village, a truck coming in the opposite direction rammed into it, Karimnagar Rural Assistant Commissioner of Police Usha Rani said.
Six people including two women were killed on the spot, while 15 others including the driver of the truck were shifted to various hospitals in Karimnagar town, she said.
Efforts are on to ascertain the identity of the deceased, police said.
Expressing grief over the mishap, Chief minister K Chandrasekhar Rao asked the officials to ensure better medical care to the victims, a release from his office said.
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