CIA chief says bin Laden in Pakistan

* Sources in Pakistan providing info on al Qaeda targets

* Says al Qaeda still most serious security threat to U.S.

(Updates with more quotes, details)

WASHINGTON, June 11 (Reuters) - CIA Director Leon Panetta said on Thursday the U.S. intelligence agency believes al Qaeda leader Osama bin Laden is hiding in Pakistan and hopes joint operations with Pakistani forces will find him.

Asked whether he was sure that bin Laden was in Pakistan, Panetta told reporters: "The last information we had, that's still the case."

Bin Laden, who has eluded a U.S. manhunt since the Sept. 11, 2001, attacks, has issued audio and videotapes over the years demonstrating that he is still alive.

Finding bin Laden is "one of our major priorities," Panetta said. "One of our hopes is that the Pakistanis move in militarily, combined with our operations, we may be able to have a better chance" to find the al Qaeda leader, he said.

Panetta said al Qaeda "remains the most serious security threat" to the United States and its leaders, particularly in Pakistan, continue to plot against America.

There are "a number of people" on the ground in Pakistan providing intelligence on al Qaeda targets to the United States, he said.

The intelligence agency also is focusing on countries where al Qaeda might find safe haven, like Somalia and Yemen, Panetta said.

Reporting by Tabassum Zakaria; Editing by Bill Trott