KUALA LUMPUR, Dec. 18 -- The Malaysian Anti-Corruption Commission (MACC) has stepped up its investigation into an international law firm that it said helped embezzle some US$1 billion (RM4 billion) in 1MDB money, as part of its ongoing efforts to recoup stolen assets and funds.

Officials estimate that as much as RM42 billion from the state investment firm was siphoned off by several actors over several years.

Up to RM29,752,034,475.13, or 70 per cent of the total stolen assets, has been recovered to date, the MACC said earlier this year.

"This law firm is believed to be involved in the embezzlement of 1MDB funds worth US$1 billion, including the wiring of around US$700 million to an offshore entity that was out of 1MDB's control," a so...