Michigan State Police troopers and other state officials will start a door-to-door sweep of Flint on Tuesday to hand out bottled water and water filters, and the White House says it is monitoring the water crisis "very closely."

The move, announced by the state Sunday, is intended to help address the ongoing water emergency in the city.

Flint's drinking water was contaminated with lead, and an unknown number of children were poisoned while the city was under the control of a state-appointed emergency manager in 2014 and 2015. The door-to-door distribution follows an announcement Saturday that water would be available free at fire stations throughout the city.

The announcement came as the White House said Sunday during "Meet the Press" that it was monitoring the situation as part of a discussion on growing mistrust in government. Denis McDonough, chief of staff to President Obama, said the White House is watching the Flint situation "very closely."

Three liaison officers from the Federal Emergency Management Agency are in Michigan assisting state officials after Gov. Rick Snyder declared a state of emergency Tuesday. The state asked for the help, but Snyder has not yet made a request through FEMA for federal financial aid, an official said Saturday.

Flint's drinking water became contaminated with lead in 2014 after its supply source was switched from Lake Huron water provided by what was then the Detroit Water and Sewerage Department to the more polluted and corrosive Flint River, while the city was under the control of a state-appointed emergency manager.

The cost-cutting move resulted in a spike in lead levels in children, which can cause permanent brain damage. A recent preliminary report from a task force appointed by Snyder placed most of the blame on the state Department of Environmental Quality, which did not require the addition of anti-corrosive chemicals to the water. That prompted a Snyder apology and the Dec. 29 resignation of the department director.

The city moved its source of drinking water back to Lake Huron water supplied by Detroit in October, but concerns about contamination remain because the more corrosive Flint River water damaged pipes and other ­infrastructure.