KABUL, Afghanistan — Early Thursday morning, Taliban fighters in southern Helmand Province launched a daring attack: They packed explosives into three stolen Humvees originally supplied to Afghan forces by the United States and drove them into Afghan security outposts. After the Humvees exploded, other suicide attackers followed.

On Saturday, the Taliban released an astonishing bit of information about that attack, which took place in the province’s Gereshk district: One of the suicide bombers was the son of their supreme leader, Mawlawi Haibatullah Akhundzada.

Although at least three Taliban officials confirmed the son’s death, the Taliban are known for making claims that frequently turn out to be baseless, and this one could not immediately be verified independently. But researchers and Taliban watchers have documented that Mawlawi Haibatullah’s son signed up for a suicide mission some time ago, and reports of his role in Thursday’s attack were spreading rapidly among Taliban fighters in southern Afghanistan. In the north, some insurgent commanders said they did not know whether the reports were accurate.

If the claim proves to be true, the willingness of a top leader’s son to sacrifice his life for the cause would be a propaganda victory for insurgents fighting against an Afghan government that is struggling to keep the families of most of its own senior leaders inside the country.

As the fighting season heats up, with violence raging in 12 of the country’s 34 provinces, the news could be a morale booster for the insurgency’s rank and file after a long period during which the Taliban leadership has grown increasingly corrupt, entangled in drug trafficking and unsettled by infighting. The episode is also expected to help Mawlawi Haibatullah, a little-known cleric with no military experience who has struggled to make his mark as the movement’s new leader. Mawlawi is a title reserved for Islamic scholars.