The son of Yemen\'s outgoing president is leading a crackdown to purge the Republican Guard, which he commands, of any rebellious officers found to be siding with anti-government protesters, a military official said yesterday. The Republican Guard is a pillar of the regime of President Ali Abdullah Saleh, and the attempts to ensure it remains loyal point to an effort to keep the regime from unravelling in the wake of a deal for Saleh to transfer power after 33 years as president. His son, Ahmad, has had dozens of members of the powerful military force arrested so far, said the official, who spoke on condition of anonymity because of the sensitivity of the issue. The Republican Guard has helped Saleh maintain power despite 10 months of protests, intense international pressure and an assassination attempt in June that forced him to leave the country for medical treatment in neighbouring Saudi Arabia. The Guard, one of the best trained elements of Yemen\'s military, has not suffered a high number of defections like some other military units whose soldiers and commanders left to join the protest movement. But with more frequent and serious acts of rebellion breaking out in other parts of the security services, the Guard\'s commanders are moving to prevent their ranks from doing the same. The official said Ahmad warned at a Guard meeting over the past week against \"copying\" the actions of others. They are searching units, barracks, and have banned the use of cell phones inside the camp, the official said. \"We will not permit copying here. Force will be the way to deal with any protest,\" the official quoted Saleh\'s son as saying. Some renegade units in other parts of the military have even locked their commanders out of military installations and demanded the removal of officers accused of corruption or involvement in the deadly crackdown on protesters. In a significant concession, the defence minister ordered the removal of a longtime Saleh confident within the armed forces, Ali Al Shater, known as one of the regime\'s strongmen. Protests by subordinates accused Al Shater of corruption and using his connections with the president to illegally amass wealth. Another sweep in search of rebellious soldiers took place within the ranks of the Central Security forces, led by Saleh\'s nephew, Yahia, according to a Central Security official, who also spoke on condition of anonymity because of the secretive nature of the security measures.