BEIJING - Law enforcers have been stepping up efforts to discover and bust cheating schemes as high school graduates are going all out in the "gaokao", or China's college entrance examinations.

China's public security authorities has launched a special operation to crack down on the sale of wireless devices used for cheating, as well as sale of self-proclaimed key to exam questions and the practice of using substitute exam sitters, according to the Ministry of Education (MOE).

So far, 23 suspects involved in the cheating attempts have been captured.

The ministry urged all students taking the tests to keep their honesty.

A total of 9.42 million students are expected to sit this year's tests from Saturday to Sunday.