A total of 40 education ministry bureaucrats landed post-retirement jobs at universities between January 2009 and last April, and half took up their positions just a day after leaving the ministry, government sources said.

As re-employment immediately after retiring from civil service could violate the law, a team at the Education, Culture, Sports, Science and Technology Ministry has begun to investigate the matter, the sources said Thursday.

Under the national civil service law, government officials are banned from facilitating the search for post-retirement jobs for other personnel and from seeking jobs in the sectors they used to supervise while government employees — a widespread practice better known as amakudari (literally "descent from heaven").