WASHINGTON U.S. Commerce Secretary Gina Raimondo said on Friday that U.S. authorities are still investigating a hack reported by Microsoft involving her emails and she would not speculate on whether China was behind it.

Raimondo was among a group of senior U.S. officials whose emails were hacked earlier this year by a group Microsoft (MSFT.O) said was based in China, according to a person briefed on the matter.

"We don't know yet the full extent of it," Raimondo said in an interview with CNN.

Asked if she believed China was behind the hack, Raimondo said she did not know and would not speculate.

"It's a significant hack. It's unacceptable, whoever did it. And we're going to investigate it fully and find out who's behind it, she said.

Secretary of State Antony Blinken made clear to China's top diplomat Wang Yi in a meeting in Jakarta this month that any action that targets the U.S. government, U.S. companies or American citizens "is of deep concern to us, and that we will take appropriate action to hold those responsible accountable," a senior State Department official said at the time.

(Reporting by Doina Chiacu; Editing by Sharon Singleton)