The Lebanese, pro-Western government of Camille Chamoun was also threatened to be toppled by growing UAR-supported domestic opposition groups. The Iraqis sent a brigade to Jordan on 13 July at Hussein's request. The Iraqi brigade's departure to Jordan gave the conspirators in Iraq, led by Brigadier Abd al-Karim Qasim, the opportunity to strike. On 14 July, an Iraqi unit stormed the royal palace in Iraq, executed all members of the Iraqi royal family, and mutilated the bodies of the crown prince and the Iraqi Prime Minister of the Arab Federation, Nuri Al-Said. Devastated, Hussein ordered a Jordanian expedition led by Sharif Nasser to reclaim the Iraqi throne, but it was recalled after it was inside Iraq. Hussein, worried about a similar coup in Jordan, tightened martial law. American troops landed in both Lebanon and Jordan as a show of support for pro-Western regimes in the region against the Nasserist tide. By October, the situation had calmed, and Western troops were recalled.