On Sunday, images of the female street vendor selling "banh ran" near The Huc Bridge in Hoan Kiem District arguing with foreign tourists went viral on social media, prompting authorities to step in.
While walking near Hoan Kiem pedestrian zone, the two foreign men bought a bag of four fried glutinous rice balls from the vendor who told them to pay VND50,000, Cong An Nhan Dan newspaper reported.
However, the tourists did not agree and asked to pay only VND25,000.
The vendor felt unhappy and resisted.
As the tourists gave her a VND100,000 bill, the vendor returned VND50,000 and walked away.
Some passers-by witnessed the incident and posted images of the vendor on social media.
The vendor admitted to the police her act was wrong and pledged not to repeat such violations in the future.
A fried rice ball in Hanoi costs from VND3,000-5,000.
Several overcharging incidents targeting foreign tourists have been recently reported.
Last week, authorities in Hanoi fined a street vendor VND150,000 for charging a pair of foreign tourists VND200,000 for a small bag of Indian jujubes, quadruple the normal price.