The boy’s age and identity have not been disclosed as a protective measure.

Duong The Hung is being detained at a police station in Hanoi’s Hai Ba Trung District pending investigation into the incident.

Hung is a resident at the 25 Lac Trung apartment building in Vinh Tuy Ward.

On Wednesday night, a family living in the same complex reported that their son had been touched in his genitals by a man in an apartment elevator.

Police and building managers later identified the culprit as Hung.

Hung, who says he is a post graduate, has admitted to his action.

In a similar case this week in Hanoi, a man was caught by an elevator camera kicking a six-year-old boy in the genitals, before seeming to wave his leg close to the boy’s face.

The boy’s parents filed a police complaint after viewing camera footage from their apartment complex in Dai Mo Ward, Bac Tu Liem District.

Police are still working on the second case and there has been no update so far.

Adults engaging in any lewd or lascivious act with people under 16 face jail terms of six months to three years in Vietnam.