Firefighters try to extinguish a fire at a slum in Dhaka, Bangladesh, in the early morning of Dec. 27, 2019. The cause of the fire is still unknown. (Photos: Xinhua)

People try to extinguish a fire at a slum in Dhaka, Bangladesh, in the early morning of Dec. 27, 2019. The cause of the fire is still unknown.

Firefighters try to extinguish a fire at a slum in Dhaka, Bangladesh, in the early morning of Dec. 27, 2019. The cause of the fire is still unknown.

People try to extinguish a fire at a slum in Dhaka, Bangladesh, in the early morning of Dec. 27, 2019. The cause of the fire is still unknown.

Locals gather at a fire site at a slum in Dhaka, Bangladesh, in the early morning of Dec. 27, 2019. The cause of the fire is still unknown.

People try to extinguish a fire at a slum in Dhaka, Bangladesh, in the early morning of Dec. 27, 2019. The cause of the fire is still unknown.

People try to extinguish a fire at a slum in Dhaka, Bangladesh, in the early morning of Dec. 27, 2019. The cause of the fire is still unknown.

Firefighters try to extinguish a fire at a slum in Dhaka, Bangladesh, in the early morning of Dec. 27, 2019. The cause of the fire is still unknown.

A man is seen at a fire site at a slum in Dhaka, Bangladesh, in the early morning of Dec. 27, 2019. The cause of the fire is still unknown.

Locals gather at a fire site at a slum in Dhaka, Bangladesh, in the early morning of Dec. 27, 2019. The cause of the fire is still unknown.