Marianne Kearney, Jakarta – Mr Andi runs a small stall selling Muslim caps on the edge of one of Jakarta's most notorious markets, Tanah Abang. Every stallholder around him is forced to pay protection money to various preman gangs, who visit their stalls on a regular basis.

The gangs also fight for control of the markets, he said. At least two major gangs operate in the Tanah Abang area: a Betawi gang and a rival group formed by the Madurese.

The Betawi gang was far stronger and turf wars often led to deaths. "A body is dumped in the river down there at least every month," he said, pointing to the back of the market. Last week, two men were killed in a market brawl near here.

During the day, shop owners sell perfume, prayer mats and Muslim caps. At night, the district becomes a parade ground for prostitutes.

In the more upmarket area of Block M, Mr Agus, who sells pirated video-CDs, also complained of having to pay off competing gangs.

Gang members patrol the markets before moving over to the karaoke clubs, which are usually fronts for bars with prostitutes, he said.