Someone might have insider-traded the $3.3 billion SoftBank-Fortress deal

WASHINGTON (Reuters) - The Security and Exchanges Commission said on Wednesday it froze assets of traders using brokerage accounts in London and Singapore to obtain more than $3.6 million in possibly illegal profits before the announcement that SoftBank Group Corp agreed to acquire Fortress Investment Group.

"The SEC's emergency action to freeze the proceeds of the traders' highly suspicious transactions within days of the public announcement ensures that the profits cannot be removed from the accounts while the agency's investigation of the trading continues," the SEC said in a statement.

SoftBank, a Japanese telecommunications giant, last month announced it would buy the US asset manager for $3.3 billion. Fortress' stock soared as much as 28% on the news.

(Reporting by Jonathan Stempel; Writing by Doina Chiacu; Editing by Chizu Nomiyama)