The US Justice Department appointed a chief prosecutor on Thursday to crack down on Covid-19 pandemic fraud, which is estimated to have cost the government more than $8 billion.

President Joe Biden welcomed the appointment of a chief pandemic prosecutor and pledged to “escalate our efforts to crack down on bad actors.”

The Justice Department, in a statement announcing the new position, said that it has already initiated criminal and civil enforcement actions involving more than $8 billion in alleged pandemic relief fraud.

Criminal charges have been lodged against more than 1,000 defendants over alleged losses exceeding $1.1 billion, the Justice Department said.

It added that more than 240 civil investigations have been launched into more than 1,800 individuals and entities for alleged misconduct with pandemic relief loans, reaching a total of more than $6 billion.

The federal law enforcement agency said it has also already seized more than $1 billion in illegally obtained Economic Injury Disaster Loans.

The person filling the new role will be associate deputy attorney general Kevin Chambers.

“The Justice Department remains committed to using every available federal tool — including criminal, civil, and administrative actions — to combat and prevent Covid-19 related fraud,” Attorney General Merrick Garland said in a statement.

The US Congress has allocated trillions of dollars of emergency financial assistance for Americans suffering from the pandemic’s economic effects.