At least 55 people were killed, most due to suffocation, in a massive fire at the AMRI hospital in south Kolkata early on Friday. Many more are believed to be trapped in the building, even as firemen, who many complained had reached the spot only after two hours, brought out the dead and injured using ropes and ladders.

"Forty bodies have been taken to the (state-run) SSKM Hospital," West Bengal Chief Minister Mamata Banerjee told reporters at the spot.

The fire broke out around 3.30 a.m. in the basement of the hospital annexe. Co-founded by the Emami & Shrachi Groups along with the West Bengal government in 1996, the hospital is locatd in the congested Dhakuria locality.

"The victims mostly got suffocated from the fumes. Many of them were in a serious condition in the ICU," West Bengal Municipal Affairs Minister Firhad Hakim said, adding that some firemen fell unconscious due to the fumes.

"The father of one of my friends was admitted in one of the upper floors. When he heard I am at the spot he called up his son and told him to ask me to rescue him. I could not do anything. I saw his burnt body," said the minister who reached the spot early.

There are around 200 beds in the affected block. "At the time of the fire, there were 160 patients, including around 40-50, in the ICU (Intensive Care Unit). Eighty percent have been rescued," a hospital spokesman said.

Fire Services Minister Javed Khan, who is supervising the rescue operations, said: "Some more people are believed to have been trapped. We have already rescued over 50 people."

An officer manning the city police control room said the fire spread fast and engulfed four floors of the building.

"The fire is under control but yet to be doused completely. My men are putting out fire in one spot only to find another area in flames. There is a lot of combustible material," said Khan.

Alleging that the firefighting was hindered due to lack of cooperation from the hospital authorities, a local resident said: "We were not allowed to enter early in the morning. Had we been allowed, more lives could have been saved."

The hospital has two other blocks in the complex where some of the patients rescued from the affected block have been transferred.

Around 25 fire engines had been rushed to the spot. The fire fighters were seen using hydraulic ladders to rescue the patients and office staff by cutting open the glasses with gas cutters.

A patient in his 50s admitted in the second floor of the affected building said he was brought down by breaking the glass windows.

"Around 4 a.m. when I had gone to the toilet I heard nurses saying that a portion of the building has caught fire. But they did not help me. Finally along with some other patients I came near a window. Then the fire brigade personnel came and rescued me by breaking open the glass windows."

"I tried to bring all my medical papers but they slipped out of my hands. I have lost them," said the sobbing patient.

Another patient said: "There was smoke. I helped many of the patients come out of their wards. But I could not bring out two seriously ill patients."

Hundreds of relatives of the patients admitted in the hospital were seen weeping and pleading with the firemen and disaster management personnel for news of their dear ones.

"We came to the hospital at the crack of dawn when we got to hear of the fire from television. We don't know what has happened to our family member," said a patient's relative.