Chief of the ward's police station, Lieutenant Colonel Le Thanh Hung, said that the cameras helped police supervise security and detect violations.

He said it was difficult to manage security in the ward as 45 per cent of its population was from outside the city. More than 1,200 families have rooms for rent.

For years, the ward was known as a "red light quarter", Hung said.

He said police began using cameras to supervise residential areas in August, 2013. Only four cameras were installed at the time.

"People used to doubt the effectiveness of the cameras and were not willing to donate money," he said.

However, more than 400 were now installed along streets, alleys and rental housing areas in the neighbourhood. More than half were paid for from residents' donations.

One resident, Nguyen Huu Toan, said a camera outside his house helped police find a thief who stole from his motorbike.

Another resident Hoang Thi Phuong Anh, who manages rental houses in Do Thuc Tinh Street in the ward, said the cameras helped prevent theft and prostitution.

"We are familiar with the cameras in my neighbourhood," she said, adding that residents did not mind being recorded, but added that "bad people are afraid of it".

She said that since a camera had been installed at her rental terrace, she could see what happened even when she was not there.

Lawyer Nguyen Duc Chanh from HCM City Bar Association said on Tien Phong (Vanguard) newspaper that police had to be careful when installing cameras because they could violate privacy.

Other wards in HCM City are now applying the model. 

VNS