A tape delivered to ABC News in Pakistan this weekend features a masked man making terrorist threats against Los Angeles and Australia.

ABC News reported that the man is believed to be Adam Yahiye Gadahn, a Californian purported to be an al Qaeda member and wanted by the FBI. The CIA said Sunday it is aware of the report but had no immediate comment about the tape's authenticity.

Counterterrorism officials believe Gadahn also may be the person on a 75-minute video given to ABC News last year in Pakistan.

The latest tape was aired on ABC's "Good Morning America" on Sunday, the fourth anniversary of the Sept. 11, 2001, attacks. The man on the tape, wearing a black turban with most of his face covered, calls the attacks of four years ago "blessed events" before making a threat against the United States.

"Yesterday, London and Madrid. Tomorrow, Los Angeles and Melbourne, Allah willing. And this time, don't count on us demonstrating restraint and compassion," the man says on the 11-minute tape.

The man on the tape goes on to call President Bush and British Prime Minister Tony Blair "liars" and issues a warning: "We love peace, but when the enemy violates that peace or prevents us from achieving it, then we love nothing better than the heat of battle, the echo of explosions, and slitting the throats of the infidels."

In a joint statement, Los Angeles Mayor Antonio Villaraigosa and Police Chief William Bratton said authorities knew of no specific, credible threat to the city.

Investigators have said Gadahn, who grew up in California, converted to Islam as a teen. He moved to Pakistan, attended al Qaeda training camps and served as a translator.