The video shows the suicide bomber mingling with hundreds of well-wishers greeting officials of the Patriotic Union of Kurdistan, or PUK, on Sunday, the first day of the Muslim holiday Eid al-Adha. A second attacker slipped into a gathering of the Kurdish Democratic Party across town.
In Baghdad, Brig. Gen. Mark Kimmitt said Tuesday the U.S. investigation has not determined who was behind the Sunday attack, although he said it could have been carried out by Ansar al-Islam or al Qaeda.
Kimmitt also said there were an average of 23 engagements a day between U.S. soldiers and Iraqi insurgents over the past week, compared with 18 the week before.
In other developments:
On Monday, the two main Kurdish parties — both U.S. allies but often at odds with each other — held a joint memorial at the largest mosque in Irbil, the heartland of the Kurdish self-rule region.
The PUK video shows only the back of the bomber's head as he joined the line. The man, apparently in his 20s or 30s, shook hands with one of the Irbil office's deputy chiefs, then stepped forward and put his hand in that of another, Shakhwan Abbas.
"That's when he blew himself up," said Azad Jundiyani, head of the PUK's media department.
The death toll in the weekend double suicide bombings in the Kurdish city of Irbil climbed to 101, the U.S.-led coalition said Tuesday.
Much of the evidence of the bombing had been removed from the KDP site by Monday. What remained was dried blood on the floors and walls, yellow prayer beads, a bloodstained telephone book, candies strewn on the floor, and pieces of clothes, among other things.
"I can only say that it's very painful to see all this," said Hoger Nader, a KDP militiaman. "I feel the blast broke our backs and destroyed our nest."
No group claimed responsibility for the attacks, the bloodiest in Iraq in six months. But Kurdish and U.S. officials blamed Muslim extremists — particularly Ansar al-Islam, an armed group that operates in the Kurdish enclave and is believed allied with Osama bin Laden's al Qaeda.
"All indications point to the involvement of Islamic terrorists with al Qaeda connections," Barham Salih, prime minister of the PUK-dominated sector of the Kurdish region, said by telephone from Washington.
Ansar al-Islam, or "Helpers of Islam," is a group of several hundred Kurdish militants who have vowed to establish an independent Islamic state in the north. It was formed in 2000 and began stepping up its activities in October 2001.
Kurdish officials say more Ansar fighters have entered Iraq since Saddam Hussein's fall.
"Our information indicates that al Qaeda was behind this ugly terrorist act," Kosrat Rasul Ali, the No. 2 man in PUK, told The Associated Press.
Brig. Gen. Martin Dempsey, commander of the U.S. Army's 1st Armored Division, told reporters that the Irbil bombings, along with a Jan. 18 attack in the capital that killed 25 people, were "different from the sort of hit-and-run style" of Saddam loyalists thought to be behind anti-U.S. attacks in Baghdad and central Iraq.
"It concerns us that it could be another enemy, a different enemy, a foreign-influenced enemy, a terrorist network enemy," he said in Baghdad.
Also in Baghdad, U.S. administrator Paul Bremer insisted Tuesday that security was improving in Iraq since Saddam was captured Dec. 13.
"I think the situation has improved importantly since the capture of Saddam Hussein," Bremer told reporters. "Every day that goes by we have more and Iraqis responsible for their own security in the Civil Defense Force and police, Iraqi army and border police."
The United States is pushing to meet a June 30 deadline for handing over power to the Iraqis and is seeking to work out differences with Iraqi leaders on creating a new government. Amid the wrangling, the Kurds are demanding to hold onto the considerable autonomy they enjoy in the north.
On Tuesday, insurgents fired two rockets at Baghdad International Airport but caused no casualties, the U.S. military said. The airport is used as a major base for the military. A command spokesman said the rockets were fired from a heavily populated area of the city.