TRENTON, N.J. (AP) – Twenty-one people in Maine and seven other states may have fallen ill after eating hamburgers possibly contaminated with E. coli bacteria, the Centers for Disease Control and Prevention said Wednesday.

CDC spokeswoman Lola Russell said three cases – two in New York and one in Florida – are confirmed as being linked to the beef, with the other 18 cases possibly linked and under investigation.

Maine public health chief Dr. Dora Mills said Wednesday night one confirmed case of E. coli poisoning in Maine is connected to the recall, according to Gov. John Baldacci’s spokesman, David Farmer.

He said the cases stretch from Farmington to Rockland.

No one has died, but Russell said she had no additional information on the cases.

Elizabeth, N.J.-based Topps Meat Co. on Tuesday announced a recall of boxes of frozen hamburgers it distributed. The recall affects 331,582 pounds of frozen beef patties and 21 products that were distributed nationwide, the U.S. Department of Agriculture and Topps said.

Russell and USDA spokeswoman Amanda Eamich said the illnesses were reported in Connecticut, Florida, Indiana, Maine, New Jersey, New York, Ohio and Pennsylvania.

The person infected in Maine “is expected to make a full recovery,” Farmer said Mills told him late Wednesday. The location of that person was not immediately available, he said.

“There are currently five other known cases of E. coli in Maine,” Farmer said. Some of those have been tested and do not match the strain in the New Jersey recall, he added. “We’re waiting for results on the others,” he said.

E. coli causes intestinal illness that generally clears up within a week for adults but can be deadly for the very young, the elderly and people with compromised immune systems. Symptoms can include severe stomach cramps, bloody diarrhea and, in extreme cases, kidney failure.

Topps spokeswoman Cortney McMahon said officials continue working to find the cause of the contamination.

“That investigation is still ongoing,” McMahon said. “Topps is going to fully cooperate with the USDA.”

Contaminated burgers were found in one New York victim’s home freezer by health officials.

The boxes recalled carry the number “Est. 9748” inside the USDA mark of inspection and were produced on June 22, July 12 or July 23, the USDA said.

The recalled products include certain 10-pound boxes of Butcher’s Best 100% All Beef Patties; certain 10-pound boxes of Kohler Foods burgers; certain 10-pound boxes of Sand Castle Fine Meat; some 2-pound boxes of Topps 100% Pure Ground Beef Hamburgers; and some 3-pound boxes of Topps 100% Pure Ground Beef Hamburgers.

The company, the leading U.S. manufacturer of frozen hamburgers, said this was its first recall in its 65-year history.

“First and foremost, Topps Meat Company is concerned with the safety and welfare of all our customers and we are deeply concerned for those who became ill,” said Geoffrey Livermore, the company’s operations vice president.

New Jersey Health Department spokesman Tom Slater said the state has four suspected cases.

Slater urged consumers to return the product to the store and immediately call their doctor if they ate the hamburgers and feel symptoms similar to stomach flu.

At least six people have fallen ill in New York, and three were hospitalized, officials said. All are recovering.

A full list of the recalled products is available at http://www.toppsmeat.com/.