A DNC bus dumped sewage in Lawrenceville, Georgia, on Tuesday, raising a stink that could result in fines after an investigation by the state's Environmental Protection Department.

The bus company operating the Democratic National Committee bus, which had been in the state to campaign for the party's presidential nominee Hillary Clinton, could face fines for illegal dumping since the incident allegedly happened on a state road and into a state storm drain,WXIA-TV reported.

The bus, marked with the slogan Democratic Party slogan "Forward Together," made the dump about 9:30 a.m. Tuesday, WAGA-TV reported.

"We'll have to talk to the charter bus company and determine what happened and why," Kevin Chambers, with Georgia Environmental Protection Department, told WAGA-TV.

State officials interviewed witnesses Wednesday in connection with the incident, where Gwinnett County hazmat crews were called to clean up the waste that the DNC bus left behind, WXIA-TV noted.

"This was an honest mistake and we apologize to the Lawrenceville community for any harm we may have caused," the DNC stated in apology for its latest leak, according to WGCL-TV. "We were unaware of any possible violations and have already taken corrective action with the charter bus company to prevent this from happening again. Furthermore, the DNC will work with the Georgia Department of Natural Resources, as well as local and state officials to determine the best course of corrective action.

Witnesses called Lawrenceville police to the O'Reilly Auto Parts store on Grayson Highway to report an "RV" illegally dumping sewage, a police report stated, according to WXIA-TV. Authorities said a large amount of drying toilet paper was on the road, leaving a "foul smell" behind, according to the station.

"You don't pull up and dump raw sewage on the street and in the storm drain," Mike Robins, the O'Reilly Auto Parts manager who witnessed the bus dump, according to WAGA-TV. "You just don't do that."