The Justice Department inquiry is said to be focused on potential antitrust violations among the country’s largest egg producers.

Americans have been attempting to smuggle eggs from Mexico and Canada due to high egg prices in the United States. Egg interceptions are up 36% in the U.S. compared to last year, according to Customs and Border Protection,

Smuggling of eggs is considered illegal in some countries as eggs which have not been formally inspected can spread diseases.

The Trump administration has called on European countries to supply eggs to the U.S., as Americans continue to face rising costs for this basic staple. The U.S. Department of Agriculture (USDA) issued the request while Trump signed new tariffs on European aluminum and steel and threatened to impose 200% tariffs on alcoholic beverages.