Al-Qaida is calling on its operatives to attack Western and Israeli interests around the world in order to avenge the deaths of Palestinians in the Gaza Strip. Ayman A-Zawahiri, considered the number two man in the international terror organization after Osama Bin Laden, called on Muslims around the globe to hit "Zionist and Crusader" targets in every location and by all available means. Israel's operation in Gaza is part of a Western attack on Islam, he said in an audio message posted on the Internet. More than 600 Palestinians, including civilians, have been killed in the Israeli military offensive in the Gaza Strip. The operation began on December 28 and aims to weed out terrorists in Gaza and end the firing of rockets from Gaza onto Israeli homes. A-Zawahiri accused United States president-elect Barack Obama of supporting the offensive. He said the operation was Obama's "gift" to the Palestinian people before he takes office. Obama broke his silence on the issue on Tuesday, saying the loss of civilian life in both Gaza and Israel was "a source of deep concern" for him. "After January 20th I'm going to have plenty to say about the issue," Obama said. What the Palestinians are facing is part of a "Zionist Crusader campaign" targeting Muslims and Islam, A-Zawahiri said. A-Zawahiri also criticized Egyptian President Hosni Mubarak, calling him a traitor for keeping the Gaza-Egypt border closed before and during the hostilities. The authenticity of the recording could not be verified. The Media Line website.