CIA Chief David Petraeus' downfall over an extramarital affair has made him the butt of jokes within the Taliban.

A Taliban official couldn’t help but laugh at the mention of the Petraeus scandal during an interview with the AFP in northwest Pakistan this week, before offering his opinion on how the four-star general, who once ran the U.S. wars in Iraq and Afghanistan, would have been punished according to the sharia.

“What a b******! But all Americans are the same, it's nothing new," the unnamed official told AFP.

"From a Pashtun point of view, Petraeus should be shot by relatives from his mistress's family," the Taliban official explained.

"From a sharia point of view, he should be stoned to death," the official summed it up making his stand very clear.

Petraeus, 60, resigned last Friday after acknowledging that he had an affair with a woman later identified as his biographer Paula Broadwell, who spent months studying the spy agency chief’s leadership of the U.S. troops in Afghanistan.

The Taliban official was of the opinion that sex scandals in the West did not surprise the people of Afghanistan. "It's quite normal for Americans and Western people to behave like this — they live in free sex societies where nobody cares about this sort of thing, so what do you expect?" he told AFP.

On Thursday, the CIA opened an investigation into the conduct of Petraeus.

"At the CIA we are constantly reviewing our performance. If there are lessons to be learned from this case we'll use them to improve,” the intelligence agency said in a statement. "But we're not getting ahead of ourselves; an investigation is exploratory and doesn't presuppose any particular outcome."

The affair that ended the illustrious career of the most prominent U.S. military figure of the post-9/11 years came to light during an FBI investigation of emails reportedly sent by Broadwell to a woman named Jill Kelley, a married Florida socialite with links to the MacDill Air Force Base near Tampa.

Gen. John Allen, the top U.S. commander in Afghanistan, has also been linked to the scandal as per the evidence turned up during the FBI probe.

Gen. Petraeus will testify Friday at Capitol Hill for the deadly attack on the U.S. consulate in Benghazi that led to the deaths of U.S. Ambassador to Libya Chris Stevens and three other Americans. The general will be questioned by lawmakers behind closed doors on the attack, which was a hot topic of contention between the Republicans and the Democrats during the presidential election campaign and also after that.