Dubai: A statement published on an Islamist Website today (March 22, 2004) purporting to be from al-Qaeda urged retaliation against the United States and its allies for Israel's killing of Hamas spiritual leader Sheikh Ahmed Yassin.

"Sheikh Yassin's blood will not have been shed in vain - we call on all the Abu Hafs al-Masri Brigades to avenge the sheikh of the Palestinian resistance by striking the tyrant of the century America and its allies," said the statement carried by the www.al-ansar.biz Website.

The Abu Hafs al-Masri Brigades take their name from an al-Qaeda leader killed in Washington's 2001 onslaught in Afghanistan and is a name regularly used in communiques from the Islamic militant network to its cells around the world.

There was no immediate way of establishing the authenticity of the latest statement.