PORT OF SWEET GRASS, Mont. - Jesse Huffman insists he didn't do it on purpose, but the toilet he left plugged after "nature called" at this border crossing in north-central Montana has him facing criminal charges.

Toole County authorities charged the 19-year-old college student from Great Falls with criminal mischief after a border agent accused him of intentionally clogging the toilet.

Huffman said the clogged piping was completely unintentional, the result of an urgent, but natural bodily function.

"I've never been arrested before or anything like that, and I get arrested for taking a dump," said Huffman, a student at Montana State University in Bozeman.

Huffman was returning to Montana from a trip to Lethbridge, Alberta with four friends Saturday. Port authorities stopped their car for what was apparently a random search. The car's 19-year-old driver was cited for illegally possessing alcohol.

Huffman said he asked to use the bathroom while waiting for the driver.

A short time later, a port inspector discovered the toilet was clogged and threatened charges, Huffman said.

Cory Grayson, one of Huffman's friends, said he couldn't believe it when border agents first threatened charges.

"I didn't think they were serious at first, I was just laughing so hard," he said.

Port Director Larry Overcast said he could not comment on the case.

Huffman said he has hired an attorney and intends to fight the charge.