Johannesburg, Apr 24 (IANS): A 25-year-old Vietnamese man was arrested here when he was trying to leave the country with three rhino horns, authorities said Monday.

The customs officers at the OR Tambo International Airport found the horns Sunday when they were searching his bags, the SA Revenue Service (SARS) said.

The horns weighed about 13.9 kg in total and had an estimated street value of 7.5 million rands (about $900,000), Xinhua reported.

The man had travelled to South Africa before and he was being closely monitored when he was arrested, SARS spokesperson Adrian Lackay said.

There has been a growing demand for rhino horn in Vietnam where it is a luxury item, used as a post-partying cleanser and a purported cancer cure. But there is no scientific proof for this.

About 180 rhinos were poached this year in South Africa, according to wildlife officials. The government has appealed to the public to assist in fighting rhino poaching.