Food truck owners in Arlington County are fighting county regulations and what they say is a spike in police enforcement that is ruining their business.

County rules now allow trucks to park and serve food for only an hour at a time. The truck must move every 60 minutes or risk a citation. And owners say county police have been issuing more citations than ever since summer.

The 60-minute limit has been in place for years, but several vendors say they've never seen officers ticket violators in all the years they've been operating in the county.

"We've been in business since last December and we never heard about or saw police giving citations until recently," said Uyen Nguyen, who owns Lemongrass Truck. "That [time restriction] really limits our amount of sales."

The truck owners are now getting help from the Arlington-based Institute for Justice. The institute doesn't typically defend clients who receive criminal citations -- which is what the vendors get -- but is helping to arrange legal representation for the owners.

"This rule makes absolutely no sense," said Bert Gall, a senior attorney at the institute. "There aren't any health and safety rules the trucks are breaking. ... It's discrimination against the food trucks."

Arlington County Police spokesman Dustin Sternbeck told The Washington Examiner that the county has been enforcing the food truck regulations for some time and often issues warnings before writing citations.

But vendors said the 60-minute limit barely gives them time to set up and serve food before they have to move again.

"The ordinance is also unclear because it doesn't specify how far we have to move," Nguyen said. "Can we just move up one or two spaces? Do we need to relocate completely?"

The business owners say they are now not only fighting to have their citations thrown out, but are working closely with the county to change the law and possibly create designated areas for the trucks to park and serve for extended periods.

Jill Griffin, a commercial development specialist at Arlington Economic Development, said the county has had "ongoing conversations with the food trucks" and is looking at options to alleviate the problem.

Changes could be in place as early as January, she said.

"We would love to be able to operate for longer," Nguyen said, "and the county has been giving us tremendous support to implement that as soon as possible."