Karachi, March 6 (IANS): The death toll from the collapse of a residential building in Karachi has increased to 18 as rescue workers retrieved eight more bodies from the rubble, officials said Friday.

The five-storey building collapsed Thursday afternoon in Rizvia Cooperative Housing Society, trapping dozens of people in the debris, reports Xinhua news agency.

Senior Superintendent of Police of Karachi Central District Arif Aslam Rao told the media that the search and rescue operation continued throughout Thursday night and was still ongoing as there were more people trapped under the debris.

"The search and rescue operations will not end till the last piece of rubble is removed," the official said.

Confirming the toll, Sohail Khan, a medico-legal officer at the Abbasi Shaheed Hospital, told Xinhua that seven women and three children were among the deceased, while at least 36 others were injured.

Rescue officials said that the operations have been difficult because the streets were narrow and highly congested, adding that they also had to be very careful in removing the rubble as they believe nearby buildings may also collapse.

A few other buildings in the area have been vacated by the authorities to prevent any further loss of life.

Additional Director of Sindh Building Control Authority Ashkar Daud told local media that the collapsed building was illegally constructed, and a strict action will be taken against those involved in illegally issuing of license for the construction of buildings.