The security agencies arrested Razaul Hasan, 22, and Ziaul Haq, 24, in Martung area of Shangla district in Khyber-Pakhtunkhwa province yesterday.
They were accused of having links to Arshad Khan and Tariq Khan, the two couriers who were killed along with the al-Qaeda leader.
The brothers were arrested from a house in Kotkai village in the mountainous Shangla district, The News daily reported today.
The brothers are the grandsons of a man named Musafar, whose brother Ahmad Saeed had settled in Kuwait long ago.
Both the slain couriers had reportedly lived in Kuwait for many years.
An unnamed local resident told the newspaper that Ahmad Saeed had been living in Kuwait for decades and his two sons had gone to Afghanistan during the Taliban regime and were killed in the ''jihad''.
He said their bodies were brought from Afghanistan and buried in a graveyard in Martung.
During the Cold War era, many fighters from Arab counties and the Pashtun region of Pakistan were recruited, trained and financed with the help of the Pakistani military.
Many militants from the Malakand region of Khyber-Pakhtunkhwa had taken part in the ''jihad'' against Soviet forces in Afghanistan.