Ex-US Attorney Preet Bharara, also fired by Trump, attends Comey hearing

Preet Bharara, a former US Attorney for the Southern District of New York, sat right behind James Comey Thursday as the ousted FBI director delivered blockbuster testimony before the Senate intelligence committee.

A source told CNN that Senator Minority Leader Chuck Schumer, D-New York, invited Bharara, who was fired along with 46 other US attorneys in March.

Bharara made a name for himself as one of the nation's most aggressive prosecutors of corruption and Wall Street crime. His presence at Thursday's hearing was particularly noteworthy in light of his frequent criticism of the President.

When Comey was fired on May 9, Bharara tweeted, "EVERYONE who cares about independence & rule of law in America should be "troubled by the timing and reasoning" of Comey firing. Period."

In the past few days, Bharara has strongly criticized the President's dealings with Comey on Twitter.

He was tweeting during the hearing as well, echoing Comey about the possibility of a taping system inside the White House.

"We can all agree with Jim Comey that, Lordy, we hope there are tapes," Bharara tweeted.