WASHINGTON -- Two top Democrats on a House committee are demanding public hearings to force top Trump administration officials to explain their costly plane travel.

Reps. Elijah Cummings, the top Democrat on the House oversight committee, and Raja Krishnamoorthi issued the letter Tuesday. Their request to Republican chairman Trey Gowdy cites recent reports of travel by Treasury Secretary Steven Mnuchin and EPA Administrator Scott Pruitt involving military aircraft that cost taxpayers tens of thousands of dollars.

The two Democrats complain that federal agencies have yet to fully respond to committee requests made last fall seeking information on the use of government-owned aircraft for personal travel or private aircraft for official travel.

Their demand comes amid growing questions over Cabinet members' spending and travel.