FRESNO, Calif. -- Investigators in Madera are searching for a suspect who assaulted a cashier and robbed him. But it's what he used to rob the clerk that's getting attention.Surveillance video shows the man wait for the clerk to open the cash register to make change, and then toss a cup of Mountain Dew in his face. The suspect then reaches into the open drawer to grab handfuls of cash."I've never seen in my time as an investigator a person throw soda at a cashier in order to facilitate a robbery," said Detective Shant Sheklanian with the Madera Police Department.And that soft drink is also the reason why investigators say they're having a tough time tracking this guy down."After interviewing the cashier, we learned he had to clean up the soda and had wiped away the surface and any latent prints that had been left behind," said Sheklanian.The suspect got away with $500.