The BBC says it has interviewed the operational leader of the Haqqani Network, the Taliban-allied militant group.

In an interview posted on the BBC website Monday, Sirajuddin Haqqani denied that his group killed Afghan peace envoy Burhanuddin Rabbani.

Haqqani also said the Haqqani Network, which has been blamed for a string of recent attacks on Western targets in Kabul, has not had recent links to Pakistan's intelligence agency, the ISI.

The outgoing chairman of the U.S. Joint Chiefs of Staff, Admiral Mike Mullen, told a Senate hearing last month the Haqqani Network acts as a “veritable arm” of the ISI, and that its fighters planned and conducted the assaults on the U.S. embassy in Kabul and on a NATO base in Afghanistan.

The BBC says a face-to-face interview was not feasible because of “security concerns.” The British broadcaster said the questions were delivered through an intermediary who returned with the audio response. The BBC says it believes the audio response is genuine.