WASHINGTON — House Republicans ground the impeachment inquiry to a halt for hours on Wednesday, staging an attention-grabbing protest at the Capitol that sowed chaos and delayed a crucial deposition as they sought to insulate President Trump against mounting evidence of misconduct.

The day after the most damning testimony yet about Mr. Trump’s pressure campaign to enlist Ukraine to smear his political rivals, House Republicans stormed into the secure office suite where impeachment investigators have been conducting private interviews that have painted a damaging picture of the president’s behavior — and refused to leave.