JINAN, April 16 (Xinhua) -- Twenty-four people have been punished for their roles in a mine accident that killed 21 people in east China's Shandong Province last October.

The rock burst accident occurred at Longyun Coal Mining Co. Ltd. in Yuncheng County on Oct. 20, leaving 21 people dead and another four injured.

High-stress mines, mining activities and lack of preventive measures are blamed as the causes of the accident, according to an investigation report released by the Shandong provincial government on Tuesday.

The company's general manager, chief engineer, and deputy general manager in charge of mining work were removed from their Party and administrative posts. The company's Party secretary was stripped of his Party post.

The other people accountable for the accident were given administrative warnings.