RAYTOWN, Mo. -- The Federal Bureau of Investigation is investigating who stole two horses with a rare disease.

Five other horses with a disease called piroplasmosis were euthanized at the Raytown Equestrian Park before the thefts.

One woman who keeps horses at the Raytown stable said it is a really sad day for the horse community.

"There are no words to describe that people who have horses know they are members of your family, not just horses, so this is devastating," she said.

Investigators said someone broke in, cut the locks and stole two of the horses that tested positive for the disease to save them from being put down.

The woman, who wished to remain anonymous, said she was shocked by the horse theft.

"The owners would not have done it. They would not have risked it," she said. But she said there are a lot of animal lovers who would do it to save two animals if they could.

The Missouri Department of Agriculture is working with local authorities and the FBI to locate the missing horses.

The disease does not affect humans, officials said. But they are concerned because it can affect the horse industry. The disease, which can make horses very weak, has no cure.

The woman who stables her horses at the park said she worries that the two stolen horses are now putting others in jeopordy. She said she doesn't want the disease to be spread further.

The disease can be passed through needles and ticks, officials said.

Anyone with information about the horses' whereabouts are asked to call police.