At least 12 people, including five women, were killed yesterday as a two-storey tin structure, housing around 20 families, collapsed in a marshland in the capital's Rampura area.

The victims along with scores of others got trapped under the wreckage when the ground floor of the makeshift structure went down in water around 3:00pm. The illegal structure was built with tin, metal bars and wood about a year ago, said locals.

At least 20 people were rescued by locals. But it couldn't be known how many still remained trapped under the debris.

A trader named Monir built the structure in Hajipara Matir Masjid Jheel where around 120 people used to live, said locals.

Syed Ibrahim Ali, a dweller on the first floor, said there were 20 rooms in the structure, and they would pay a monthly rent of TK 4,500-5,000 for each room.

Maj Shakil Newaz, acting director general of Fire Service and Civil Defence, said, "The rescue operation might take quite some time, as the rescuers had to make holes in the sunken floor to get to the bottom."

Nine units of fire service were conducting the operation. The team of 50 rescuers included three divers. 

Twelve bodies were recovered as of 1:30am today, said Rampura police.

Md Anwar Hossain, deputy commissioner (Motijheel zone) of Dhaka Metropolitan Police, said the dead include six men and five women.

Seven of the deceased were identified as Mizan, 45, his wife Kalpona, 40, and their daughter-in-law Roksana, Harun-ur-Rashid, 45, Karuna Begum, 55, Runa Akhtar, 18 and her brother Zakir, 50. The identity of the rest couldn't be known immediately.

Garment worker Nasreen Akhtar said her husband Khokon Hawladar, younger sister Runa and elder brother Zakir were in the house on the ground floor when the structure collapsed. 

Khokon first rescued four trapped children of his neighbours. He then tried to rescue his sister-in-law Runa but failed to hold on to her arms. Khokon was out of breath and about to drown. Luckily, the rescuers came to his aid and saved him.

Nasreen said her sister, also a garment worker, was to leave in the evening for their village home at Kathalia in Barisal to see their elderly parents. She was supposed to board a launch from Sadarghat terminal.

GM Jainal Abedin Bhuiya, chairman of Rajdhani Unnayan Kartripakkha, admitted that it is their responsibility to prevent construction of such illegal and risky structures for housing.

Asked why they didn't perform their duty in this case, he said, "We will think about it from now on … and will try to warn the dwellers about the danger."

In response to a query why Rajuk doesn't remove such illegal and risky structures, he said such action would create humanitarian problems. Besides, the poor dwellers of such structures are integral to city's economic activities. 

Jainal said Rajuk has not yet taken up any scheme to provide the urban poor with safe and affordable housing.

Around a hundred illegal makeshift structures still stood around Hajipara Matir Masjid Jheel.   

Noted urban researcher Salma A Shafi said such risky structures are built randomly to be used for housing for the urban poor across the capital.

It is the duty of Rajuk and local government representatives such as councillors to prevent construction and use of such illegal and risky structures for housing purposes, she said.

"Unfortunately, housing for the urban poor has been nobody's liability for long though they contribute greatly to the city's economic development," said Salma, who has worked for rehabilitation and betterment of the urban poor over the last three decades.