DETROIT (AP) — A judge has declared a mistrial in a dispute over partial liability for Flint, Michigan’s lead-contaminated water. The jury couldn’t reach a unanimous verdict after hearing months of evidence against two engineering firms. Veolia North America and Lockwood, Andrews & Newman were accused of not doing enough to get Flint to treat the highly corrosive water or to urge a return to a regional water supplier. The jury deliberated for roughly seven days after hearing evidence for months. The trial involved four Flint children who consumed the water. It became contaminated in 2014-15 because water pulled from the Flint River wasn’t treated to reduce the corrosive effect on lead pipes. Separately, the state is paying $600 million of a $626 million settlement with residents.