Between 1970 and 1971, Lin Biao and his counterrevolutionary clique intensified their attempt to usurp the supreme Party and state power, plotting to assassinate Mao Zedong and stage a military coup. After their scheme was exposed, on September 13, 1971, Lin Biao and a few of his supporters boarded a plane and tried to flee the country. The plane crashed in Undur Khan in the People?s Republic of Mongolia. Lin Biao died in the crash. The remains of the plane are shown here.