Ahead of public hearings next month, the chiefs of staff and other aides to the members of the House Select Committee were warned to prepare for bombs.

The warning came on a weekly call with committee staff, according to two sources that were on the call. A security meeting with the US Capitol Police is scheduled for May 20 to prepare lawmakers and their staff for the public hearings which are due to begin on June 9.

The January 6 committee issued subpoenas for House Minority Leader Kevin McCarthy, as well as other congressmen.

It's not clear how the committee will enforce the demand if Republicans don't comply with it by the end of the month.

Jamie Raskin, who serves on the January 6 committee, believes his Republican colleagues will cooperate with the investigation.

We have every reason to believe that members of Congress will comply with their legal and moral duty to participate.

Sources on the January 6 call did not say if the committee would issue more subpoenas.