Bomber hits memorial for Karzai's half-brother

Updated at 5:24 a.m. Eastern

A suicide blast tore through a packed mosque in the southern Afghan city of Kandahar on Thursday as mourners offered prayers in a service for Ahmed Wali Karzai - the region's most powerful man and a half-brother of the Afghan president - who was murdered at his home days earlier.

CBS News' Fazul Rahim says Afghanistan's Interior Ministry confirmed the blast and said there were at least five people killed, but the number and extent of the injuries was changing as the situation unfolded.

There were reports of a second explosion even as people surveyed the damage from the first blast, but few details were available and police would not confirm the reports. Local media reported the explosion was from a remotely detonated mine planted in a nearby neighborhood, aimed a patrolling police, but the details could not be confirmed.

The service for Wali Karzai was a second memorial, following a formal funeral on Wednesday when President Hamid Karzai climbed into his half-brother's grave and beseeched insurgents in Afghanistan to stop killing their fellow countrymen.

Interior ministry spokesman Sediq Seddeqi told Rahim it was a suicide attack carried out inside the mosque.

At least five people were killed in the blast, according to the Kandahar governor's office, including two prominent religious scholars who headed regional clerical councils. At least 15 others were injured in the explosion.

Seddiqi said none of the president's family members were injured in the attack.

There was no immediate claim of responsibility for Thursday's bombing.

The man who shot Ahmed Wali Karzai was from his own tribe and hometown and traveled with and worked beside him for seven years.

Afghan officials say it's not clear whether he was killed by insurgents, as the Taliban claimed, or died as the result of an internal dispute.

"Although corrupt, he was effective, and he turned the recent (U.S.) surge of troops and money to great effect in Kandahar, where the Taliban have been under great pressure over the past year," says Logan.

"They were not pleased by the growth in Wali Karzai's power -- it threatened their hold on their Pashtun heartland."

Taliban spokesman Zabiullah Mujahid issued a statement Wednesday saying that insurgent fighters killed Wali Karzai because he cooperated with U.S., British and Canadian forces in the south.

"He was aligned with foreign occupiers," who bombed Afghan villages, Mujahid said.

The Taliban spokesman called Wali Karzai a "puppet" of the West and alleged that he was on the CIA payroll and profited from the illegal seizure of government and private land.

Wali Karzai had denied working for the CIA or being involved in shady business dealings.