At least six people, including women, were killed in a major fire that broke out in a multi-storey commercial complex in Secunderabad here on Thursday evening, officials said.

A senior police officer said the cause of death would be known after investigation but, most likely, inhaling smoke could be the reason.

"We have information that six persons have died," the officer said, adding the fire has been brought under control.

Twelve people were admitted to different hospitals and six of them died during treatment at one of the hospital, the officer said, adding the rest were still undergoing treatment.

The victims belong to Warangal and Khammam districts of Telangana. They were employed in a marketing company which had an office in the complex, officials said.

According to a witness, the fire started at around 7.30 pm in the complex that houses several offices.

More than 10 fire fighting vehicles, including four fire engines, were rushed to the spot to extinguish the blaze as huge flames leapt out from one of floors of the eight-storey building earlier.

Another official supervising rescue operation said till midnight, there was still a lot of smoke coming out of the building and it will take some time for it to subside.

Rescue personnel were scouring the area to look for anyone still trapped inside, he said.

A preliminary investigation suggested short-circuit to be the reason behind the blaze, said the official.

Three people were killed in a major fire in a five-storey commercial building in Secunderabad this January. The fire ravaged building was subsequently demolished.