BEIJING, May 31 (Xinhua) -- A senior Chinese police officer Sunday urged public security organs at all levels to ensure public order during the upcoming Children's Day and the national college entrance examination in early June.

"Security measures in kindergartens and schools must be fully implemented and loopholes must be found out," said Vice Minister of Public Security Huang Ming at a video conference.

A string of attacks has shocked the country over the past few months and school security has been tightened. Police nationwide have began a thorough inspection of schools and nurseries, especially private ones and those in rural and remote areas, to close security loopholes.

"Public security organs at all levels must work with kindergartens and schools to ensure that kids will have a safe and happy Children's Day," Huang said.

Huang stressed that the permanent mechanism for the safety in kindergartens and schools should be established.

He also urged police officers to clamp down on cheating activities with high-tech devices during the college entrance examination, as well as criminal behaviors that disturb the examination and its participants.