The capital city's Department of Education started in 2007 to give urine tests to students who were thought to be more inclined to use drugs, such as those who were depressed, frequently absent from classes or had friends with complicated backgrounds.

Some 26 students from junior high and senior high schools were found to have used drugs in the first year that the plan was implemented.

In the following year, over 80 students tested positive. This year until October, a total of 99 students were found to have used drugs, of which nearly 90 percent were male students. Some 86 percent of the students used ketamine with cigarettes, and nearly eight percent of the students used amphetamine, said officials.

According to education officials, the schools provided three months of counseling for the students who tested positive for drugs. Students will be removed from the counseling program when their subsequent tests show negative. All students who tested positive and were enrolled in the program this year have left the counseling program, added the officials.