A father accused of poisoning his children's soup in a scheme to sue the Campbell Soup Co. was indicted on tampering and fraud charges, authorities said.

The children, a 3-year-old boy and his 18-month-old sister, were taken to hospital emergency rooms three times in January.

According to investigators, their father fed them tainted soup each time. On the third occasion, authorities said, he used the prescription drugs Prozac and Amitriptyline — both used to treat depression — making his young daughter so ill she was flow by helicopter to an Atlanta hospital.

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William Allen Cunningham, 40, was charged with tampering with consumer products with reckless disregard for the risk that another person would be placed in danger of death or serious bodily injury. He also was charged with mail fraud, wire fraud and communicating false statements that a consumer product had been tampered with.

U.S. Attorney David Nahmias said Cunningham wanted to get money from the manufacturer by claiming its soup caused his children's illnesses. Cunningham contacted Camden, N.J.-based Campbell by mail and phone to complain, but there was no evidence the soup was tainted when it was purchased, Nahmias said.

The children are now in the custody of their mother, who has not been charged, he said. He declined to comment on their health.

Cunningham was expected to appear before a federal judge next week. If convicted, he could face up to 75 years in prison. Cunningham remained jailed Friday and had no lawyer on record.