A pair of radioactive goldfish have been found swimming in a lemonade pitcher in the bowels of the Perry nuclear power plant.

Their presence in a steam tunnel after a 43-day plant maintenance shutdown has led reactor owner FirstEnergy Corp. on a hunt to find the owner.

The fishy tale has prompted federal regulators to ask a lot of new questions about morale at Perry and whether plant operators can control access to radioactive areas as required by regulation.

"Clearly somebody brought the two goldfish into the plant. They did not swim into the plant," said Perry spokeswoman Jennifer Young.

Though fish do occasionally turn up in power plants, pulled in with cooling water from rivers or lakes, Young said investigators are pretty sure these two came in through the front door, probably in a plastic bag in someone's pocket.

Security checks of employees involve detection of metal and bombs, not fish in plastic bags. Employees and contractors are not patted down and not subject to body scans, said Young.

Crews taking down scaffolding in an underground steam tunnel at the plant found the fish earlier this week and immediately filed a report, as required federal regulation.

Young said investigators were questioning employees and contractors and reviewing video recordings of the tunnel.

The tunnel contains lines that carry super-heated steam from the reactor building to the adjacent turbine building, which houses the plant's steam turbine and electrical generator. The tunnel is off-limits as a radiation area when the reactor is running.

Waste in the bottom of the pitcher convinced investigators that the fish had not been in the container for very long, Young said.

Chemists in Perry's laboratory quickly determined that the clear water in the pitcher was reactor water - and that the fish and the water were only slightly radioactive, due to the long maintenance shutdown.

"The radioactivity was slightly above environmental detectable limits," said Young. "Had it been any less, they would not have been able to detect it."

Still, early Thursday morning, both of the 11/2-inch-long fish died.

"They did not have exposure to enough radioactivity to hurt them," Young said. "It was probably due to lack of care before they got to the plant. The radiation could not have killed them."

The Nuclear Regulatory Commission on Thursday had more questions than answers.

"This is not something that happens every day. We want to know why it happened and how it happened," said Viktoria Mitlyng, NRC spokeswoman for the agency's Midwest region. "We are looking at the potential implications."

Because of a life-threatening incident during refueling two years ago at Perry in which three contractors were briefly exposed to hard radiation, the NRC has put the plant under a microscope on the issue of worker safety. The agency was already preparing to send squads of inspectors to the plant in June in an effort to determine whether Perry has corrected past shortcomings. Extra inspectors were at the plant earlier during this shutdown.

The company and the NRC said this latest incident is no laughing matter, as in the cartoon TV series "The Simpsons" in which Blinky, an orange fish, supposedly had three eyes from radiation exposure. Whoever was involved in the Perry incident will not get off as easily as nuclear worker Homer Simpson usually does.

"We know everybody who had access to the tunnel. Also we have video because we had video cameras trained on that area as a security measure," Young said.