Reince Priebus, the former chief of staff to President Donald Trump, was interviewed for a full day Friday by members of special counsel Robert Mueller's team, Priebus's lawyer said.
In a statement, William Burck said his client was interviewed voluntarily.
"He was happy to answer all of their questions," Burck said.
The interview, which took place at the special counsel's office in Washington, is a sign that Mueller's investigation is now reaching into the highest levels of Trump's aides and former aides.
Priebus served as chairman of the Republican National Committee during the 2016 election campaign before joining the White House when Trump was...