KARACHI, Pakistan - A massive fire swept through a four-star hotel in the southern port city of Karachi on Monday, killing at least 11 people, officials said.

More than 50 people suffered injuries in the early morning blaze, which started in the hotel kitchen, police officer Tauqeer Naeem said.

An exact cause of the fire was not yet known, he said, adding four of those killed were women.

Dr. Semi Jamali at Karachi's Jinnah's Hospital said some foreigners were among those being treated for burns. Suffocation caused more deaths, she said.

Most of Pakistan's buildings don't meet safety standards to avoid such mishaps.

TV footage of the incident showed guests at the hotel using bedsheets to climb down from windows.

A man standing at a balcony kept waving for help but the hotel didn't have any means to reach him, a survivor, Hamid Ali, told a local Pakistani TV channel.

He said the guests were sleeping when the fire broke out.