Islam religious authorities have detained a singer for dressing too "sexily" during a performance, media reports said today.

Siti Noor Idayu Abdul Moin, 22, told the Star she was wearing a sleeveless top and long trousers when state religious officials raided the performance venue on Tuesday.

"Our band had just finished and it was a little past midnight when they came in and rounded up all the Muslims," she said.

Siti was among seven people detained overnight after the raid, which opposition leaders said marked a "disturbing trend" in multiracial Malaysia.

The singer said the officers initially accused her of consuming alcohol - which is taboo for Muslims - and drugs and being involved in immoral activities, but a breathalyser test proved negative.

"The officers finally wrote me a notice accusing me of dressing sexily and encouraging immorality just because I sang there," she said.

Opposition Leader Lim Kit Siang called Siti's detention a "disturbing trend" that showed the "narrow and intolerable face of Islam."

He said it undermined Prime Minister Abdullah Ahmad Badawi's efforts to promote a moderate form of the religion known as Islam Hadhari.

Malaysia's population of more than 26 million people is 60 percent Malay, 26 percent Chinese and eight percent Indian. Malays are defined as Muslims from birth.