WASHINGTON -The government has obtained a new video of Osama bin Laden marking the sixth anniversary of the September 11, 2001, attacks and is analyzing it, a counterterror official said today.

Several intelligence agencies were looking at the video – the first new images of the terror leader in nearly three years – but no details or conclusions about its message were immediate available, the official said. The counterterror official spoke on condition of anonymity because of the sensitivity of the issue.

The video ended Mr. bin Laden’s longest period without a message. The Al Qaeda leader has not appeared in new video footage since October 2004, and he has not put out a new audiotape in more than a year.

The Department of Homeland Security said yesterday it had no credible information warning of an imminent threat to America, and analysts noted that Al Qaeda tends to mark the September 11 anniversary with a slew of messages.

Al Qaeda’s media arm, Al-Sahab, announced Mr. bin Laden’s new message in a banner advertisement on an Islamic militant Web site that included a photo of him.

“Soon, God willing, a videotape from the lion sheik Osama bin Laden, God preserve him,” the advertisement read, signed by Al-Sahab. Such announcements are usually put out one to three days before the video is posted on the Web.

One difference in his appearance was immediately obvious. The announcement had a still photo from the coming video, showing Mr. bin Laden addressing the camera, his beard fully black. In his past videos, Mr. bin Laden’s beard was almost entirely gray with dark streaks.

Mr. bin Laden’s beard appears to have been dyed, a popular practice among Arab leaders, the director of the SITE Institute, a Washington-based group that monitors terror messages, Rita Katz, said.

“I think it works for their (Al Qaeda’s) benefit that he looks young, he looks healthy,” Ms. Katz said.