Pennsylvania State Police were hunting on Wednesday for thieves who stole about 100,000 organic eggs from a wholesaler's warehouse over the weekend, a haul worth more than $40,000 retail amid a national shortage that has caused prices to surge.

Pennsylvania State Trooper Megan Frazer, who is investigating the case, told Reuters that in her dozen years on the force she has never before encountered an egg theft.

"The only thing close was 10 years ago when someone stole a trailer full of chickens," she said.

"This is a major felony, given the value of what was taken," she said of the theft that happened Saturday in Greencastle, Pennsylvania, about 65 miles (105 km) southwest of Harrisburg, the state capital.

Egg prices have soared more than 50% since last year nationwide, according to a consumer price index report on Friday from the U.S. Bureau of Labor Statistics. Farmers are contending with a bird flu outbreak that has forced them to cull millions of hens to try to stop the disease's spread.

More than 13 million hens have been slaughtered or lost since December, according to the U.S. Agriculture Department's latest egg markets overview.

The average cost of eggs was $5.29 a dozen in late January, up from about $3.50 around the same time last year, NBC reported, citing the NIQ consumer research group.

Some store shelves are bare and the ubiquitous breakfast restaurant Waffle House has imposed a 50-cent surcharge per egg, multiple media have reported.

The stolen eggs were taken from a trailer at Pete and Gerry's Organics warehouse shortly before 9 p.m. on Saturday, the police report said. A spokesperson for the company did not immediately respond to a request for comment.