China's education authority has instructed schools across the country to tighten security, barring entry to school grounds during the upcoming holiday to anyone carrying a gun or a knife at a time when the horror of the Virginia Tech slaughter is fresh in people's minds.

Security guards should step up patrols on campus and around student dormitories and enforce strict entrance checks during the week-long May Day holiday that begins May 1, said a circular released by the Ministry of Education on Saturday.

"Accidents are more likely to happen during the holidays when there are fewer students and teachers on campus," said the circular, asking school authorities to tighten safety control to prevent incidents with mass participation and serious accidents.

Schools are told to mend "security loopholes" in classrooms, libraries, labs, canteens and dorms for students or teachers in and out of the campus.

Schools should also ensure their fire extinguishers function well and fire escapes in buildings are not blocked, the ministry said.

The ministry warns school officials that they will be held accountable if campus crimes or accidents occur due to slack implementation of safety measures.

According to official figures, the number of crimes in China's primary and middle schools decreased 19.7 percent in 2006 compared with the previous year, as security departments bolstered the police presence around schools.

But the government also admitted that 43 students were killed in criminal acts at schools across China from January to September last year.

In May 2006, a 19-year-old villager broke into a kindergarten classroom in central China's Henan Province where 21 children were having classes. He locked the door and set fire to the classroom with gasoline.

Three children died and 14 others were injured in the arson attack.