Police said the workers had failed urine tests for drug abuse.

Fourteen men escaped but police later arrested 11 after a tense stand-off. Another 17 were detained over the weekend.

The protests in the central Malaysian town of Nilai came just over a month after 2,000 illegal Indonesian immigrants rioted and set fire to a detention centre in southern Malaysia.

PM's warning

Prime Minister Mahathir Mohamad was reported on Friday as saying Malaysia may employ Indonesians last when deciding between workers of different nationalities.

"Indonesian workers have been giving us many problems, sneaking into the country, when caught they become violent, we cannot accept such behaviour," he was quoted by the official Bernama news agency as saying.

Malaysia has between 700,000 to one million foreign workers, mainly from Indonesia, India, Bangladesh, Thailand, Burma and the Philippines.

Estimates put the number of illegal immigrants in the hundreds of thousands.

The Malaysian Government announced last year it would deport 10,000 Indonesian illegal immigrants each month.

It says their presence has led to a growth in crime and fewer jobs for locals affected by the economic slowdown.