CHICAGO – Members of the Dave Matthews Band have offered to provide DNA samples to help authorities get to the bottom of whether raw sewage from its bus was dumped into the Chicago River.

A lawsuit by Illinois’ attorney general contends the band’s tour bus emptied its septic tank while crossing a grated bridge over the Chicago River on Aug. 8. A tour boat was passing beneath the bridge and more than 100 passengers were doused with raw sewage.

The band issued a statement on its Web site saying members have offered to provide DNA evidence to help authorities determine the source of the sewage.

In its statement, the band also said that if its bus is found to be responsible for the incident, the band will “work quickly to make amends, with the people on the boat and with Chicago.”

“We care deeply about what happened to the people on the boat that day, which was terrible, and the damage that occurred to Chicago’s environment,” the letter states.