KABUL (AFP/Reuters) - A senior commander of the Taliban-allied Haqqani network in Afghanistan who is also the uncle of its leader has been captured, the Nato-led International Security Assistance Force said Saturday. Security forces detained Haji Mali Khan, uncle of Siraj and Badruddin Haqqani and the senior Haqqani commander in Afghanistan, Isaf said in a statement.Khan was captured close to Afghanistans porous border with Pakistan in Paktiya province Tuesday, it added, hailing the detention as a significant milestone in disrupting Haqqani operations. He was heavily armed but submitted ... without incident or resistance, Isaf said. It did not detail how they had identified Khan. He reportedly worked directly under Siraj Haqqani, and managed bases and had oversight of operations in both Afghanistan and Pakistan, Isaf said. Mali Khan moved forces from Pakistan to Afghanistan to conduct terrorist activity. Jalaluddin Haqqani consistently placed Mali Khan in positions of high importance. Haqqani is a member of the Talibans supreme council but his son Sirajuddin now effectively runs the network. The Taliban denied that Khan had been captured. I have just spoken with Haji Mali Khan, he is fine and is somewhere else and hasnt been detained, spokesman Zabihullah Mujahid told Reuters. This is a baseless news and it has been released in order to weaken Mujahideens morale, he said. Members of the Haqqani network declined to comment on the Isaf statement, but confirmed to Reuters that Khan is Sirajuddin Haqqanis maternal uncle. They said he was not a senior commander but his relatives are involved in the Haqqanis fight against Nato forces in Afghanistan. Isaf said that Khan had acted as an emissary between the Al Qaeda-linked Pakistani Taliban chief Baitullah Mehsud and Haqqani leaders. Mehsud was killed by a US drone strike in Pakistan in 2009. A spokesman for Afghanistans intelligence agency the National Directorate of Security (NDS), Lutfullah Mashal, confirmed the capture but gave different details of his relationship with the networks leader. We know that he is a member of Sirajuddin Haqqanis family but we are not sure if he is the immediate cousin. He is maybe the cousin of Sirajuddin Haqqanis cousin, he said. I am not sure if he was really an active Haqqani commander, he added, referring media queries back to ISAF. A senior Western security source speaking to AFP on condition of anonymity said the name of Haji Mali Khan was not familiar as that of a leading insurgent figure. A Pakistani intelligence official, however, said Khan was closely involved in the affairs of the Haqqanis, and managed the groups links with other militant organisations in Pakistans tribal areas. This is a blow for the Haqqanis, the Pakistani official said, requesting anonymity because he was not authorised to speak to the media. The Haqqani network has been blamed for a string of attacks in Afghanistan, particularly in the capital Kabul, where US ambassador Ryan Crocker said it was behind a 19-hour attack on September 13 which targeted the American embassy. In an interview Friday, US President Barack Obama did not endorse Mike Mullens accusations about Pakistan and the Haqqanis but said Islamabad has got to take care of this problem.