Former FBI director James Comey testified before US lawmakers for the first time in over a year Friday, with much of the discussions centering on Hillary Clinton's email use.
The closed-door grilling came amid mounting intrigue over Special Counsel Robert Mueller's investigation into Russian interference in the 2016 election and possible contacts between Donald Trump's presidential campaign and Moscow.
Comey had pleaded for a public hearing after he was subpoenaed by the outgoing Congress in November, but House Republicans including some of Trump's allies insisted on a private session before the judiciary and oversight committees.
Comey was questioned as part of a Republican-led House inquiry into possible Russian interference, and Clinton, who lost to Trump in 2016, featured prominently.
Clinton had set up a private email server before becoming secretary of state in 2009. Republicans seized on the revelation years later, saying she broke department protocol by using a private email account while a government official in order to hide sensitive correspondence.
In May 2017 Trump abruptly sacked Comey, who was the senior official leading a criminal investigation into possible collusion with Moscow.
Three months earlier the president met privately with Comey and urged him to end the investigation into former national security advisor Michael Flynn, a move that many Democrats interpreted as obstruction of justice.