Special DIA task forces were set up to monitor crises such as the Soviet invasion of Afghanistan, the overthrow of Iranian monarchy, and the taking of American hostages from the U.S. embassy in Tehran in 1979. Also, of serious concern were the Vietnamese takeover in Phnom Penh, the China–Vietnam border war, the overthrow of Idi Amin in Uganda, the north–south Yemen dispute, troubles in Pakistan, border clashes between Libya and Egypt, the Sandinista takeover in Nicaragua, and the Soviet movement of combat troops to Cuba during the signing of the Strategic Arms Limitation Treaty II.