A broad Chinese hacking campaign against U.S. telecommunication networks targeted the phones of Republican presidential nominee Donald Trump and his running mate, Sen. JD Vance, two sources familiar with the matter say. Another source told NBC News that people affiliated with the campaign of Vice President Kamala Harris were also targeted.

The targeting of the Republican presidential ticket’s phones is part of what appears to be a wide-ranging effort to gather information about American leaders.

The major spy operation is said to have attacked dozens of others, including a Wall Street Journal reporter.