Security guards lift up a security line as a student leaves a high school after she finished one of the crucial College entrance exams earlier this month. Pic: AP.

BEIJING (AP) — The college admission office in a Chinese province says at least 127 students hired other people to take the all-important college entrance exam on their behalf.

The Higher Education Admission Office in central Henan province promised a full investigation into the scam after state broadcaster China Central Television ran an expose piece on Tuesday.

Almost all Chinese high school graduates must take the college entrance exam if they wish to advance. The scores are the key criterion for what tier of university they can enter.

Education authorities typically impose strict rules to guard against cheating.