Police in Kien Giang Province have detained two men for extorting money from a sixth-grade child.
Nguyen Duc Tai and Nguyen Van Hieu, both 20 and residents of the province, are facing charges of appropriating others' property.
Another boy, 14-year-old Nguyen Quoc Dinh, is also involved in the case, but he is not old enough to be held criminally responsible.
Police said they will take approriate action against Dinh later.
From early February to April, Tai, Hieu and Dinh made T., a student from Duong Dong I Secondary School on Phu Quoc Island, give them money many times by threatening to slit his throat.
T. had to steal between VND200,000-800,000 (US$10.52-42) each time from his parents before his mother discovered the theft and asked him to tell the police.
Commander Nguyen Van Thong from Phu Quoc Police said this kind of robbery had never occurred in Phu Quoc before.
He advised parents to keep a close watch and make sure their children did not show off a lot of money in public.
Tai and Hieu are also accused of deliberately causing injuries as they and Dinh fought over their share of the money on April 8, during which Hieu slashed Dinh with a knife.