The number of drug users over 21 dropped 3.2 per cent.

Heroin remained the most popular drug, although the number of users slipped 9.5 per cent.

A 48.5 per cent drop was recorded in the number of Ecstasy users, of whom there were 331.

A hot topic at the meeting was the recent case of a group of students suspected of using drugs at school.

Commissioner for Narcotics Sally Wong Pik-yee said a series of activities to spread anti-drug messages among young people was planned during the summer holidays.

'We wish to recruit the youth to take part in healthy and interesting contests and take the opportunity to educate them,' Ms Wong said.

Among the activities were a dance and music competition with anti-drug messages that started on June 3 and a mobile phone game to be launched next month.

Ms Wong said a new drug education kit would be distributed to schools to warn students against cross-border drug use. The kit is designed for students from Primary Four to Form Three.

Ms Wong suggested parents play a more active role in drug prevention with their children.

'Parents are our important partners in the war against drugs,' she said. 'A parent seminar will be held on June 23 to equip parents with basic drug knowledge as well as skills to handle drug-related problems.'

Four schoolgirls, aged 13 and 14, were arrested on Monday on suspicion of using ketamine at the Fanling Government Secondary School. Two 17-year-old boys were arrested on suspicion of supplying the ketamine.

The case has prompted calls for a crackdown on student drug use and setting up of more outreach services.