(Reuters) - A federal judge on Wednesday removed Michigan Governor Rick Snyder, a former mayor of Flint, along with the state government from a list of defendants in a class-action lawsuit over the Flint water crisis.

The Flint Water Plant tower is seen in Flint, Michigan, U.S. on February 7, 2016. REUTERS/Rebecca Cook/File Photo

The lawsuit, brought by a dozen residents of Flint and three local businesses, involves 13 claims related to a decision in 2014 to pipe water from the Flint River, instead of water provided by Detroit Water and Sewerage.

The water from the Flint River was more corrosive than Detroit’s, and rife with lead and bacteria. By the time Flint reverted to using the DWSD, some residents of the largely African American city, including children, showed evidence of lead poisoning.

According the 128-page opinion by U.S. District Judge Judith E. Levy, “Lead poisoning caused plaintiffs to suffer from severe medical problems with their hair, skin, digestive system, and organs, as well as brain and other developmental injuries including cognitive deficits, among other issues.”

In the opinion, Levy dismissed the governor, former Flint Mayor Dayne Walling and other state and municipal officials from the suit.

State Treasurer Andy Dillon, former Michigan Health and Human Services director Nick Lyon, two former emergency managers of the city and others were kept as defendants.

A representative of the governor declined to comment on the dismissal. Neither Walling nor Dillon responded to a request for comment. Representatives of the state and a lawyer for the plaintiffs did not immediately respond to requests for comment.

During the period from April 2014 until October 2015 when water was sourced from Flint River, “some government officials disregarded the risk the water posed, denied the increasingly clear threat the public faced, protected themselves with bottled water, and rejected solutions that would have ended this crisis sooner,” Levy said in the opinion.

According to the document, the plaintiffs did not allege Gov. Snyder knew about the dangers of the water in Flint River when he authorized the switch to using it, unlike other defendants who they said knew and disregarded the hazards involved. For this reason Levy dismissed him as a defendant.

Different lawsuits related to the crisis are also pending in at least seven different state and federal courts throughout Michigan.