DETROIT (CN) - The FBI has joined the investigation into the Flint, Mich., water crisis that has federal, state and city officials all struggling to explain their delay in taking action.
In addition to the FBI, the investigation includes help from the U.S. Postal Inspection Service and the Environmental Protection Agency's Office of Inspector General and Criminal Investigation Division.
A representative for the U.S. Attorney's Office in Detroit would not confirm whether the investigation was criminal or civil, however, the Detroit Free Press reported.
With the U.S. House Oversight Committee scheduled to hold its first hearing about the water crisis Wednesday, it is uncertain whether former Flint Emergency Manager Darnell Earley will accept the invitation to testify.
Earley stepped down as Emergency Manager of the embattled Detroit Public School system on Tuesday.
Michigan Attorney General Bill Schuette drew criticism last week about the team he assembled to probe the crisis.
One of its members, former Wayne County Prosecutor Todd Flood, donated money to Gov. Rick Snyder's campaign. Flood has reportedly said he also donated to former Democrat Gov. Jennifer Granholm.
Andrew Arena, former director of the Detroit FBI office, is also part of the team. Arena led an investigation into former Detroit Mayor Kwame Kilpatrick who was eventually jailed on corruption charges.
Schuette, a Republican expected to run for governor in 2018, initially declined to look into the Flint water crisis but changed direction in mid-January after he said more information had become available.
He said the special team was appointed to avoid a conflict of interest. Schuette has called it an "outrage" that Flint residents have to pay for water they can't drink, an issue that has already spawned multiple lawsuits.
Flint's drinking water system was poisoned from lead pipes in 2014 after the a state-appointed emergency manager switched the city's water supply from the Detroit water system, Lake Huron, to the corrosive Flint River as a cost-cutting move.
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