Alloyed together with Hasina, Bangladesh's now-former prime minster who fled to India after being toppled by a revolution in August; all those under the scanner would comprise her son, Sajeeb Wazed Joy, and niece, British parliamentarian and government minister, Tulip Siddiq, whom she had made a part of her inner circle.
A writ pertaining to calling the investigation was filed in high court by Hasina's political opponent, Bobby Hajjaj, chairman of Nationalist Democratic Movement party.
"We are looking for justice through our court", Hajjaj told AFP on Monday.
Major charges relate to the financing of the $12.65 billion Rooppur nuclear plant, the South Asian country's first, which is financed by Moscow with a 90 percent loan.
A statement Monday from the commission said it had launched an inquiry into allegations that Hasina and family members had "embezzled $5 billion" from the Rooppur plant via "various offshore bank accounts in Malaysia".
It said its investigations were examining "questionable procurement practices related to the overpriced construction" of the plant.
"The allegations of kickbacks, mismanagement, money laundering, and even possible abuse of power raise grave concerns about the integrity of the project and the use of public funds", the commission said.
Graft allegations also include theft from a government building scheme for the homeless.
Hasina, 77, fled by helicopter on August 5 into exile in India, infuriating many Bangladeshis determined that she face trial for alleged "mass murder".
It was not possible to contact Hasina for comment.
Siddiq has "denied any involvement in the claims" accusing her of involvement in embezzlement, according to a statement from the British prime minister's office.
Joy, who is understood to be based in the United States, was also unavailable for comment.
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