"WASHINGTON: A top al-Qaeda operative has been captured while organising terrorist operations in Iraq, and a top deputy to another al-Qaeda linked figure was seized in a separate action a week earlier, US officials disclosed on Friday.

"These are significant developments," said a US official, who asked not to be identified. "Both of them point to stepped up efforts on al-Qaeda’s part and other extremists to launch terrorist attacks in Iraq."

Hasan Gul, a Pakistani veteran of al-Qaeda operations, was captured on Thursday in Iraq where was believed to be scooping out the turf for organising al-Qaeda operations in the country and working with like-minded extremists.

"He is a very significant player," the official said. "He’s a long time facilitator of al-Qaeda operations in terms of moving both people and money. He has an extensive network of contacts all over the world."

Gul was believed to have worked in the past with captured al-Qaeda leader Khalid Sheikh Muhammad and had connections to people, involved in the bombings of US embassies in East Africa.

In another major break, US forces captured Husam al-Yemeni, the leader of an Ansar al-Islam cell in Fallujah, on January 15, said another US official. "He is the most senior Ansar al-Islam person that’s been caught to date," said the official.

Al-Yemeni is considered the number two to Abu Musab al-Zarqawi, a Jordanian with links to al-Qaeda who has emerged as the leader of Ansar al-Islam, a militant group originally based in Kurdistan but which US military officials has established operations in the Baghdad area.

Zarqawi, who has a $5 million bounty on his head, is wanted among other things in connection with the October 28, 2002 murder of US diplomat Laurence Foley in Amman.

The official said that the information about al-Yemeni’s capture had been closely held as interrogators worked to produce other leads.

Zarqawi, whose real name is Fadel Nazzal al-Khalayleh, is still at large, the official said. It was unclear where al-Yemeni was seized or what actions his cell in Fallujah was involved in.

US officials said then that Zarqawi took refuge in Iraq after US-led forces drove the Taliban from power in Afghanistan, and received medical attention there.

"Abu Musab al-Zarqawi has had a long-standing connection to senior al-Qaeda leadership and appears to be highly regarded among al-Qaeda and a close associate of Osama bin Laden and Saif al-Adel," the State Department said last October when it posted a bounty for information leading to his capture.

Al-Adel, for whom there is also a reward, is thought to be bin Laden’s number-three and was reportedly in Iran.