Kids give a West Philly mail carrier a fright with a homemade explosive.

The young punks put a homemade bomb in the mail lady's mail bag, but luckily someone was kind enough to warn her.

Thursday afternoon, a 42-year-old female mail carrier was working her route on Farson Street in West Philadelphia when she passed by a group of kids hanging out on the block, police said.

She was up on a front porch, delivering some mail, when she saw two of the kids lift the flap of her unattended mail cart, throw something inside and run off, police said.

As the carrier huffed back to her cart, somebody yelled, "Get away from it. It's gonna blow up."

Then the cart exploded. Its flap flew open and sprays of liquid and shreds of paper blew out, police said. The mail carrier called 911. Police arrived quickly, snatching up the suspected mail-cart-bombers, both of whom were 13-years-old. One of the kids lived on the street.

The mail carrier was taken to Presbyterian Hospital where she was treated for breathing difficulty.

Police recovered a plastic bag at the scene, believed to contain the ingredients the kids used to pull their dangerous prank, some house cleaning liquids, aluminum foil, an empty plastic water bottle and cord.

The two teens got themselves charged with aggravated assault. How they know how to make a homemade bomb is another matter.