The Federal Investigation Agency registered a case against former ambassador to the United States Husain Haqqani, sources said on Monday.
The case was registered in the Anti-corruption circle by the FIA in relation to the Memogate scandal, sources revealed.
According to sources, Husain is accused of embezzlement in the secret fund worth $7.2 million.
The FIA asked the Foreign Ministry for details on the Pakistani embassy to investigate the matter further, sources added.
In February, the Supreme Court issued arrest warrants for the production of former ambassador of Pakistan to the US in relation to the Memogate scandal.
In the hearing, the apex court had directed secretaries of the interior and foreign ministers, as well as the FIA chief, to furnish a report on Haqqani's return in one week.
Responding to reports of the warrants, Haqqani stated on Twitter that it was "sad that highest court of Pakistan persists with such antics for local TV news coverage. Such political 'warrants' have not been honored abroad in the past, won't work now".
The Memogate scandal erupted in 2011 when Pakistani-American businessman Mansoor Ijaz claimed to have received an 'anti-army' memo from Haqqani, the then-Pakistan envoy in Washington DC, for US joint chiefs chairman Admiral Mike Mullen.