Career diplomat Marie Yovanovitch describes with outrage the 'smear campaign' against her in testimony as Trump attacks her on Twitter

'This is an all-hands-on-deck moment. We're taking the fight to Trump directly," the former New York mayor tweets; focus on Arizona, Michigan, Pennsylvania and Wisconsin

He is sixth Trump aide or adviser to be convicted of charges brought as part of special counsel Robert Mueller’s Russia investigation

As Marie Yovanovitch gives public testimony in probe, Trump tweets against her, says everywhere she went 'turned bad'

US president contradicts his own aides, GOP leadership, who insist remaining American soldiers will continue fight against Islamic State

Democrats say House session revealed a US president abusing his office for political gain, while Republicans insist that witnesses gave testimony that was secondhand at best

President avoids sensitive issues like Turkish offensive against US-allied Kurdish forces or Ankara's purchase of Russian S-400 missiles

Master Sgt. Roddie Edmonds defied a Nazi command to identify which of his fellow American soldiers were Jewish; We are all Jews,” said Edmonds, who was not Jewish

Schiff denies Republican request for whistleblower to give closed-door testimony; envoy says US president was overhead asking about probes he wanted Ukraine to open

As televised hearings start, US president's go-it-alone stance comes face to face with long-established system of checks and balances laid out in the Constitution