Vietnamese rejoiced Sunday after their country won its first ever Olympic gold medal, a victory made all the more sweet by the fact that regional rival China was beaten along the way.

Hoang Xuan Vinh, a 41-year-old serving army colonel who first learned to shoot with AK47 rifles, made history in Rio overnight when a near-perfect final shot in the men's 10-metre air pistol clinched him gold.

Vietnamese state media reported that Vinh would receive $100,000 from the state on his return -- a handsome sum in a country where the average annual income is around $2,100.

Vinh's victory shunted Brazil's Felipe Almeida Wu and China's Pang Wei into second and third respectively, something that was seized on by jubilant Vietnamese.

"So proud! But the greatest happiness was that we won over China," Nguyen Cao Ky Duyen, a Vietnamese music show host based in the US wrote on Facebook.

"You are the pride of the nation and the people," added reader Truong Tran Hoang Du, on the Tuoi Tre newspaper's website.

Vietnam's state media said Hoang Xuan Vinh learned how to shoot in the communist country's military which he joined in 1991, initially practising on AK47 rifles.