Kabul, Afghanistan (CNN) -- The guard who killed the half-brother of Afghan President Hamid Karzai, had for years worked with International Security Assistance Forces against Taliban militants, according to three local officials with direct knowledge of the dealings. 

Sardar Mohammed, who authorities say shot and killed Kandahar's provincial council chief Ahmed Wali Karzai, received training from ISAF and participated in intelligence gathering against militants across the region, according to Besmellah Afghanmal, a provincial council member with close ties to the Karzai family. 

He "was one of the trusted commanders for the Karzais," Afghanmal told CNN. "Sardar Mohammad was working with American Special Forces closely and he was participating in many operations with American Special forces against the Taliban in (the) south." 

Others, like provincial parliament member Hashim Watanwal, say Mohammad had worked with both U.S. and Canadian forces in Kandahar -- an ethnically Pashtun dominated region long-considered the Taliban heartland. 

Baz Mohammed, a Kandahar tribal elder with close connections to the Karzai clan, said the guard was "a trustworthy person" who collaborated regularly with ISAF in Kandahar. 

An ISAF spokeswoman declined to comment on the claims. 

Though suspected of corruption and opium dealing, Wali Karzai was considered a major power-broker in Afghanistan's restive south and a bulwark for his brother against the Taliban militancy. 

His death Tuesday sent shock-waves across Afghanistan's political landscape, and prompted President Karzai to weep as mourners gathered for his half-brother's burial the following day. 

Saidkhan Khakrezwal, a member of the Kandahar provincial council, said he and others were with Wali Karzai when the guard came into the room and asked to talk to him.  QUESTIONS:

Q1:
1. Who lost his life?
2. Whose life was cut short?
3. Who was murdered?
Q2:
1. Who lost his life?
2. Whose life was cut short?
3. Who was murdered?
Q3:
1. Who was the half-brother of the Afghan president?
2. Who was Hamid Karzai's half-brother?
3. What was the name of the half-brother of Hamid Karzai?
Q4:
1. Who killed Wali Karzai?
2. What was the name of the man that shot and killed Wali Karzai?
3. Who murdered Wali Karzai?
Q5:
1. How did Wali Karzai die?
2. How did Sardar Mohammad kill Wali Karzai?
3. How was Wali Karzai killed?
Q6:
1. Was Wali Karzai known to his killer?
2. Did Sardar Mohammed know Wali Karzai?
3. Was Sardar Mohammed familiar with his victim before shooting him?
Q7:
1. Was Sardar Mohammed known to be a terrorist?
2. Was Sardar Mohammed a known terrorist?
3. Did Sardar Mohammed have a reputation as a terrorist?
Q8:
1. Were people with Wali Karzai when he was shot?
2. Was anyone in the company of Wali Karzai at the time of his shooting?
3. Did Wali Karzai have others around him when he was killed?
Q9:
1. How did the Afghan president react to Wali Karzai's death?
2. What did the Afghan president do in response to his half brother's murder?
3. What was Hamid Karzai's reaction to Wali Karzai's death?
Q10:
1. Had Sardar Mohammed worked in the past with US forces?
2. Had there been a past collaboration betweeen Sardar Mohammed and US forces?
3. Had Sardar Mohammed previously joined forces with the United States military?
