BEIJING - Chinese police captured more than 550,000 suspects in cracking over 470,000 drug-related criminal cases between 2005 and 2011, according to the latest figures.

With the International Day Against Drug Abuse and Illicit Trafficking falling on Tuesday, the Ministry of Public Security announced on Monday that police seized more than 150 tonnes of illegal drugs in the seven years.

China had 1.79 million registered drug addicts as of the end of 2011, a big increase from about 1.44 million in June last year, the statistics from the ministry's Narcotics Control Bureau show.

About 998,000 drug addicts, or 55.6 percent of the total, were aged 35 or under.

Among all the addicts, 64.5 percent consumed heroin while 32.7 percent used new types of drugs such as methamphetamine or ketamine.

Altogether, 1.62 million drug users underwent quarantined rehab between 2005 and 2011, while about 210,000 people were required to go to community rehabilitation centers, according to the bureau.