A former employee of a Philadelphia McDonald’s says he captured a mouse scurrying inside a bag of Big Mac hamburger buns in a cellphone video, Fox 29 reports.

Karruim Demaio, who worked at the West Oak Lane fast-food restaurant until this month, says he was so disturbed by what was happening, he wanted to warn customers.

In the video is a bag of hamburger buns used to make Big Macs. Inside that bag, a mouse is scurrying around, making contact with who knows how many buns.

"I was going back there to get something else and I heard some rustling, so I turned around, and I look, I seen a mouse inside the bread. Not on top of the package, but inside of the package,” Demaio said.

In the video, the brown object in the center-right of the screen is apparent. You can see the tail come into focus as the mouse squirms between the buns.

Click here for more on this story and to watch the raw video from MyFoxPhilly.com.

Fox 29 spoke to another former employee who did not want to be identified. He says he was fired for not showing up to work. That employee confirmed what Demaio told the station.

"I was working there from October of 2010 to January of this year. There hasn't been a time when we couldn't go in the back and see mouse droppings on the bread," Demaio said.

Demaio told Fox 29 his boss ordered employees to brush off the droppings, and serve the bread to customers.

What's more, that former employee says he once saw the general manager brush off the droppings herself.

Fox 29 contacted the owner of the McDonald's franchise and he initially said he did not watch the station’s report, but later sent out a statement.

"After viewing the video, we are going to continue to investigate this claim to make certain we have all the facts. I want my customers to know that I am taking this matter seriously and will immediately address any issues that may exist. Therefore, if necessary, we will work with the appropriate authorities to get the facts," said Ken Youngblood, McDonald's owner/operator.