The last stand of the army of the ill-fated Khmer Republic in any form took place around the Preah Vihear Temple in the Dângrêk Mountains, close to the Thai border. Remnants of the FANK's 9th Brigade Group occupied the area for a few weeks in late April 1975, following the collapse of the Lon Nol regime. Even though their government had surrendered, FANK soldiers continued to fiercely hold their ground for nearly a month after the fall of Phnom Penh against several unsuccessful attempts by Khmer Rouge forces to reduce this last holdout. The Khmer Rouge finally succeeded on May 22, after shelling the hill where the temple stands, scaling it, and routing the defenders, as Thai officials reported at the time.