OKLAHOMA CITY (AP) -- Christian-oriented Hobby Lobby Stores Inc. filed a federal lawsuit Wednesday challenging a mandate in the nation's health care overhaul law that requires employers to provide coverage for the morning-after pill.

The lawsuit by the Oklahoma City-based chain claims the government mandate is forcing the company's owners "to violate their deeply held religious beliefs under threat of heavy fines, penalties and lawsuits." Failure to provide the drugs in the company's health insurance plan could lead to fines of up to $1.3 million a day, the company said.

"By being required to make a choice between sacrificing our faith or paying millions of dollars in fines, we essentially must choose which poison pill to swallow," David Green, Hobby Lobby CEO and founder, said in a statement. "We simply cannot abandon our religious beliefs to comply with this mandate."

Hobby Lobby calls itself a "biblically founded business" that is closed on Sundays. Founded in 1972, the company now operates more than 500 stores in 41 states.

Kyle Duncan, general counsel for the Becket Fund for Religious Liberty, said 27 other lawsuits have been filed nationwide over the mandate, mostly by nonprofit groups

"This mandate violates the religious liberty of millions of Americans," Duncan said. "The government has turned a deaf ear to the rights of business owners."

Hobby Lobby is the largest and only non-Catholic-owned business to file a lawsuit against the Health and Human Services mandate that forces all companies, regardless of religious conviction, to cover the morning-after pill.

The pill works by preventing ovulation or fertilization. In medical terms, pregnancy begins when a fertilized egg attaches itself to the wall of the uterus.

If taken within 72 hours of unprotected sex, it can reduce a woman's chances of pregnancy by as much as 89 percent.

Critics of the contraceptive say it is the equivalent of an abortion pill because it can prevent a fertilized egg from attaching to the uterus. Recent research suggests that's possible but not likely.

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