A Memphis grandmother is behind bars after being arrested for sneaking drugs into a prison, police said. But, she claimed she was tricked.

According to the arrest affidavit, Sarah Griffin, was bringing a bag of Doritos to her grandson Cody Clements in jail. She thought a cellphone was inside, but police said it was something much more dangerous.

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One of the officers asked to see the chip bag. Clements took a small black object out of the bag.

The officer took the unknown object from Clements and, noticed it was wrapped in electrical tape. They unrolled the bag and found marijuana, meth, Xanax pills and heroin, police said.

Griffin told deputies she did not know there were drugs inside the bag. Griffin said she picked the Doritos up from a girl earlier in the week and thought a cellphone was inside.

Sarah Griffin, 68, is charged with contraband in penal institution, among others.