Hong Kong, March 30 (DPA) Children as young as 11 are crossing Hong Kong's border into China to take drugs, a church group said Friday.

Six children aged between 11 and 13 admitted to regularly travelling to the Chinese border city of Shenzhen where they can buy party drugs such as Ketamine for half the price as in Hong Kong.

The group were among 128 drug-users, who travel across the border to feed their habits, interviewed by Evangelical Lutheran Church of Hong Kong. Around half of them were under 17.

The figures show an increase in the number of young cross border drug-users, said a church spokesperson.

A similar survey four years ago found 30 percent of cross-border drug-users under 17 and one in the 11-13 age group.

The problem of young people crossing the border to China for drugs has escalated since the border opening hours were increased to 24 hours in the years following the handover when Hong Kong reverted back to China.

Official figures released earlier this month by the Action Committee Against Narcotics show the number of young Hong Kong people taking drugs has increased by 12 percent in the last year.

Reported drug-users aged under 21 grew from 2,276 in 2005 to 2,549 last year, bucking the general trend which saw the total number of drug-users drop by 6.4 percent from 14,113 to 13,204 over the same period.

One in 10 of all drug-users took drugs across the border in discos and karaoke bars with 39.6 percent of these aged under 21.

In December, 120 youngsters from Hong Kong were detained by police in Shenzhen after a raid on a disco. The group were held for 15 days for drug abuse after drugs were detected in their urine.