Officials in Michigan filed a lawsuit on Wednesday accusing a French company and a Texas firm of negligence and fraud for their roles in the lead water contamination crisis in the city of Flint.

Michigan Attorney General Bill Schuette said water engineering firms Veolia, based in Paris, and Lockwood, Andrews & Newman (LAN) of Texas ignored warning signs that dangerous levels of lead had seeped into the city's water, after government officials switched the supply source two years ago.

The attorney general alleged that Veolia produced a report and a presentation in 2015 which incorrectly stated that Flint's drinking water was safe.

He also said LAN was supposed to help with the transition to the new water source and did not address the issue of corrosion in aging lead pipes.

"Veolia and LAN were hired to do a job and failed miserably. Their fraudulent and dangerous recommendations made a bad situation worse," Schuette said in a statement.

Both companies denied the accusations.

"These allegations are entirely false and baseless, something that Veolia will have no trouble in proving since the city of Flint never tasked it with carrying out lead or copper tests," the company said. It added that an official state task force report did not hold Veolia responsible.

LAN said the suit was "without merit" and that the attorney general "blatantly mischaracterizes the role of LAN's service to Flint."

In 2014, government officials switched Flint's water source from the Detroit River to the Flint River as part of cost-cutting measures ordered by Governor Rick Snyder.

Experts believe that was the reason large amounts of poisonous lead leached from the city's pipes into the drinking water that reached residents' homes.

"Veolia and LAN either knew or should have known that high chloride levels in Flint River water would cause corrosion in lead pipes unless treated," the attorney general's office said.

More than 8,000 children are believed to have consumed lead-contaminated water.

Officials are asking for hundreds of millions of dollars in damages and said there could be additional claims in the future.

"Today's civil lawsuit is the first step in seeking damages caused by these companies that can help with Flint's recovery and aid the residents of Flint who are still waiting for help," Noah Hall, Special Assistant Attorney General on the Flint investigation, said.

So far in the attorney general's six-month investigation of the Flint water crisis, three government employees have faced criminal charges. One took a plea agreement to cooperate in the investigation.

The damage to the city's water pipes may be long-lasting, if not permanent. Residents must use filters to make their water drinkable.

So far, more than 19 million liters of bottled water have been distributed in Flint, according to state figures.