A state organization that investigates animal cruelty is putting up a reward for information leading to whoever burned a cat and staked it to a tree stump in a south Minneapolis park.

The treatment of the cat, which was found before dawn Monday by a Longfellow Park employee, is being treated by federal authorities as a possible threat against President Obama because an Obama-Biden campaign lawn sign was left standing near the stump, and the animal was pierced in the neck with the stick of a handheld American flag.

"This despicable act of animal cruelty will not go unpunished," said Tim Shields, general counsel for the Minnesota Federated Humane Societies, which offered the $1,000 reward. Shields added that an arrest could lead to felony charges.

The Minnesota Federated Humane Societies investigates cruelty cases and trains, certifies and appoints state humane agents.

Agencies that responded to the incident included the Secret Service, the FBI, the federal Department of Homeland Security, officers from the Minneapolis park police and the Minneapolis Police Department.

PAUL WALSH