KANDAHAR, Afghanistan -- President Hamid Karzai survived an assassination attempt Thursday by an Afghan security guard who fired on his convoy, and a large explosion in the capital killed at least 10 people. Afghan officials blamed Osama bin Laden's al-Qaida network for both attacks.

The Afghan president's American bodyguards opened fire in response to the shooting in Kandahar, and three people were killed, including one who was wearing an Afghan military uniform. Their bullet-riddled bodies could be seen outside the grounds of the mansion in a pool of blood.

In Washington, a Pentagon official said an American bodyguard in Karzai's security detail was wounded but that he didn't know how serious the wound was.

"Terrorists are behind both attacks, there is no doubt about it. And terrorists in this region are led by Osama and his associates," said Afghan Foreign Minister Abdullah.

Near anniversary

The attack in Kandahar occurred as the convoy carrying Karzai and Kandahar Gov. Gul Agha Sherzai was leaving the governor's mansion. Sherzai, who was grazed in the neck, was released after being treated at the U.S. air base here.

The violence was the most serious assault against the Afghan leadership since it took power following the collapse of the Taliban last year. It occurred less than a week before the anniversary of the Sept. 11 terror attacks and four days ahead of the anniversary of the assassination of military leader Ahmed Shah Massood, who was killed by al-Qaida.

Massood's Tajik-controlled northern alliance, which had battled the Taliban for five years, became the major power in Karzai's government. It is opposed by Pashtuns, who dominate the south, where Thursday's assassination attempt took place.

The Pashtuns, the largest ethnic community and the Taliban's former political base, have grown increasingly frustrated by the Tajiks who dominate the new administration.

Karzai was in Kandahar, the former spiritual headquarters of the Taliban, to attend a wedding celebration for his youngest brother, Ahmed Wali Karzai.

"I was just outside the gate when I heard the gunshots," Sherzai's security chief Dur Mohammed said. "The Americans opened fire on three people, and they were killed."

After the attack, Karzai returned to the governor's guesthouse, where he is staying, and said he was fine.

"He says he is safe and sound, and has come to expect these things," said BBC reporter Lyse Doucet, who was with the president at the time of the attack.

She said thousands of people were pressing forward toward the president and one Afghan boy approached his vehicle.