More than 4,000 units of police, tanks, police dogs and others responded to different mock scenarios in an anti-terror exercise in downtown Saigon on Sunday. 

Ho Chi Minh City authorities rehearse ways to handle security disturbance situations deploying different units in District 1 and the Tan Son Nhat International Airport.

Burning cars and vehicles are dealt with during the exercise.

In District 1, the hypothetical situation has hundreds of people driving motorcycles, holding long sticks and banners, screaming and attacking state officials.

Security forces spray water cannons and disperse the crowd. Meanwhile, the sound of explosions and gunfire could be heard. 

Within a radius of nearly one square kilometer, the streets of Hai Ba Trung - Nguyen Dinh Chieu - Nam Ky Khoi Nghia - Nguyen Du - Pham Ngoc Thach and Le Duan in District 1 and District 3 are blocked for the drill to take place.

An armed tank with sniper patrols a street.

In another situation, a terrorist group occupies the District 1 People's Committee head office and holds people hostage, threatening to set off chemical explosives.

Hundreds of armed police move ahead in formation to the people's committee headquarters to rescue hostages.

A police officer climbs a wall to enter the building.

Police dogs participate in the terrorism drill.

Firefighters go into action during the drill fires.

Police arrest troublemakers after hours of negotiations and attacking.

Emergency medical staff are in attendance to tend to injured victims and transfer them the hospital.

The drill, organized by the HCMC Counter-Terrorism Committee, ended after three hours. The exercise deployed many specialized equipment for the first time.   

Under the Vietnamese law, the maximum penalty for terrorism, or conducting activities to overthrow the government is death.