WASHINGTON (Reuters) - Officials at the U.S. Capitol had to “sweep” a secure conference room to check for security breaches such as listening devices after Republican lawmakers stormed in to protest the Democratic-led impeachment inquiry into President Donald Trump, two sources said on Thursday.

A source from one of the committees conducting the inquiry said the House of Representatives Sergeant at Arms and other security personnel conducted the sweep before witness Laura Cooper could testify.

The protest by Republicans delayed Cooper’s deposition by about five hours on Wednesday, but did not otherwise affect the investigation schedule.

Interviews that had been planned for Thursday and Friday were put off because of memorial events for Representative Elijah Cummings, the Democratic chairman of the House Oversight Committee, who died last week.