CHICAGO (CBS) — Gas prices for the Fourth of July are the highest in four years, according to AAA.

AAA says the national average for one gallon of regular gas is $2.86.

In Chicago, the average price for one gallon of regular gas is $3.09.

Experts blame high crude oil prices for the increase, however, prices are still 11 cents cheaper than gas prices over Memorial Day weekend.

The Feds are cracking down on credit card skimmers at gas pumps this Fourth of July. Secret Service agents are inspecting pumps nationwide, looking for devices which allow thieves to steal customers’ banking information.