CCTV camera footage shows that the four men, traveling on two motorbikes, stopped on Vo Thi Phai Street in Thoi An Ward, District 12, Friday morning after they saw a dog wandering around.
Even as the dog's owner, Nguyen Huu Duc, approached, one of the men used a stun gun on it. As Duc tried to stop them, they threatened to attack him. When he stepped back, another member of the gang picked up the unconscious dog and all four made their escape.
"I cannot believe they'd dare to do so in broad daylight," Duc said, shocked and in grief at losing a dog that has been with him for 10 years.
He has reported the incident to the local police along with the CCTV footage, which he also posted online.
Vietnam consumes an estimated five million dogs a year, second only to China's 20 million. Many dogs served at restaurants are stolen pets sold to small, unregulated abattoirs, it has been reported.