The Federal Investigation Agency (FIA) has summoned former foreign secretary Sohail Mehmood in connection with the cypher audio probe, 24NewsHD TV channel reported on Thursday.

According to sources in FIA, a notice has been served on Sohail Mehmood to show up at the agency headquarters on October 28.

Sohail Mehmood was called at 12 noon, the insiders said, adding that a second summons was also served on former secretary Muhammad Azam. He is too called 

to the FIA headquarters on October 28.

Last month, a leaked audio tape purportedly of Pakistan’s former Prime Minister Imran Khan surfaced in which he is talking about how to exploit the controversial cypher to portray his ouster in April as a conspiracy.

The clip features a conversation between Imran Khan and Azam Khan. The chairman of his Pakistan Tehreek-e-Insaf (PTI) was ousted from power in April after losing a no-confidence vote in his leadership. But he alleged the not-trust vote was part of a US-led conspiracy targeting him because of his independent foreign policy decisions on Russia, China and Afghanistan.

US Assistant Secretary of State for Central and South Asia Donald Lu was the central figure in Imran Khan’s claims about a US-backed regime-change conspiracy. Washington denied any role in his ouster.