FRESNO, Calif. (KFSN) -- A new lawsuit raises questions about the source of a rare cancer in Fresno. Warren Paboojian is suing Fresno County after he says ten people, including a retired judge, developed blood cancer after working in the criminal courthouse between 1966 and today.

"Yeah, I think it's a cancer cluster. What we have at the courthouse is a cancer cluster," Paboojian said. The attorney says his clients all had regular exposure to an underground gas pump in the courthouse parking structure before developing cancer.

Action News obtained photos of the pump called the "Courthouse Motor Pool." County documents reveal it connects to a 10,000-gallon underground gas tank. "It's at the B-1 level," Paboojian said.

"It's one level below the main floor." Paboojian says the pump and tank have leaked chemicals into the ground and produced toxic fumes in the air. One of the chemicals is benzene, a major component of gasoline and a chemical the government says is known to cause cancer.

In a statement to Action News, county officials wrote: "The fueling station located in the garage of the Courthouse has been regularly maintained and monitored by the County and by State agencies since its installation." Officials say the most recent inspection was on August 8. The county adds inspections take place weekly, monthly, and annually and says all inspections are in good standing and no items have been noted that need repair.

Paboojian says the county will not hand over any records, so .