Nearly $2.5 billion has been sent this week to victims of a massive fraud case in the U.S.

Court authorities said Thursday they mailed checks averaging about $2 million to 1,230 investors who were defrauded by one-time financial manager Bernard Madoff. The investors were victims of Madoff's long-running Ponzi scheme in which he collected more money from new investors to pay off earlier ones, until the scheme fell apart.

The latest payout to Madoff's victims brings their total recovery to more than $3.6 billion. Court trustee Irving Picard has recovered about $9 billion of more than $17 billion he believes was lost by Madoff and is considering the claims of other investors.

Madoff was arrested in late 2008 and pleaded guilty three months later. Now 74, Madoff is serving a 150-year term at a U.S. prison.