Hackers linked to China electronically stole documents from a Washington law firm, Interpol and a Hong Kong bank that were then published online in a bid to discredit a dissident wanted by Beijing.
FBI agents are conducting an investigation into the cyber attack earlier this month that penetrated information systems at the law firm Clark Hill, according to people familiar with the investigation.
Private cyber investigators later traced the cyber attack to China and South Korea.
The hacking and release of sensitive documents on Twitter mirrors the Russian intelligence operation to sway the outcome of the 2016 presidential election in what U.S. intelligence have dubbed a cyber-enabled influence operation.
Until recently Clark Hill represented the dissident, Guo Wengui, who is a major target of the Beijing government after he began publicly speaking out about high-level corruption among Chinese leaders earlier this year.