The number of juvenile delinquents prosecuted increased by 50 percent, said the official, without giving a specific figure.

About one in 10 criminals detained and prosecuted in 2006 was underage, said the official.

"There is a visible increase in gang crime among juvenile delinquents and crimes have become more violent," the official said. "This is a major issue which endangers social stability."

Theft, robbery and assault are the three major types of juvenile crime, accounting for 98 percent of the total, said the official.

Wu Heping, spokesman of the Ministry of Public Security, said in April that preliminary statistics showed many juvenile delinquents had been negatively influenced by the Internet.

"In a high proportion of robbery, sexual assault and fraud cases involving young people, the Internet is a factor," Wu said.

Also on Thursday, a spokesman with the Supreme People's Court said that more than 430,000 defendants under the age of 18 were convicted on criminal charges in China from 2000 to 2006.

The spokesman said China had set up 2,420 juvenile tribunals, which could handle almost all juvenile criminal cases.

He said the juvenile tribunals paid great attention to protecting the legal rights of the accused minors.

"Education and correction, rather than punishment, has always been China's core principle in dealing with juvenile crimes," the spokesman said.