(Bloomberg) -- The Texas county that includes Houston suedVolkswagenGroup of America Inc. for $100 million, claiming the carmaker’scheating on emission controls worsened pollution in the area.It’s believed to the the first government claim stemming from theVW emission scandal, according to county officials.

The county is seeking penalties of as much as $25,000 a day foran estimated 6,000 diesel-powered Volkswagen autos sold there since2009, Vince Ryan, the county attorney, said in an e- mailedstatement.

“The number of tampered vehicles could increase as the countycontinues its investigation,” Ryan said. Each vehicle soldconstitutes a violation a day, according to the complaint.

The county is parsing sales tax rolls and may seek sales recordsto determine the exact number of suspect diesel-powered autos soldduring the target period, Sarah Utley, assistant county attorneyfor environmental enforcement, said in a phone interview.

Numbers in the complaint are “very gross estimates” based onHouston’s proportional share of nationwide sales of thoseVolkswagen models, given that Harris County is the heart of thefourth-largest city in America, she said.

Other counties

Utley said Harris Countyis reaching out to other major urban counties in Texas to see ifthey’d like to participate in the litigation. The county will alsocoordinate with a multistate investigation into the automaker bystate attorneys general, including Texas, she said.

“It’s hard to know what’s going to happen, because a lot dependson how Volkswagen handles it,” Utley said. “Their actions were sointransigent and horrendous, and it was shocking that they got awaywith for so long. Their plan was evil-genius brilliant until theygot caught.”

Jeannine Ginivan, Volkswagen’s U.S. spokeswoman, declined tocomment on the lawsuit since it is litigation in progress.

The sprawling Houston area, home to the U.S.’s largestconcentration of petrochemical plants and refineries, suffers frompoor air quality exacerbated by “massive” traffic congestion, Ryansaid.

Ozone emissions

Pollution regulators have classified the county as anon-attainment zone for smog-causing ozone emissions for years, andthe excessive nitrogen oxide emitted by Volkswagen’s faultyvehicles contributed to that problem, Ryan said in a complaintfiled Tuesday in state court in Houston.

The county sued in conjunction with the Texas Commission onEnvironmental Quality, which regulates air pollution.

The U.S. Environmental Protection Agency cited Volkswagenthis month for outfitting diesel vehicles with software thatlowered engine emissions during testing but allowed them to soar toas much as 40 times allowable levels under normal drivingconditions.

Harris County also sued Audi of America LLC for allegedly faultyemissions controls on Audi A3 models sold in the area, according tothe complaint. The diesel-powered sport sedan was listed in theEPA’s notice of violation alongside five Volkswagen models.

The case is Harris County v. Volkswagen Group ofAmerica, 2015-57864, 234th Judicial District of Harris County(Houston).

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