PHILADELPHIA (CBS) — Philadelphia police are investigating a robbery early Monday morning at an SPCA office in the Juniata Park neighborhood.

The thief got away with a safe containing about $2,000 and an SPCA truck.

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Police say a man in his 20s entered the office, in the 100 block of West Hunting Park Avenue, about 4 AM, claiming he had an injured dog.  He then pulled a knife, according to police, and demanded money.

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Police say he put the safe in an SPCA animal rescue truck that was outside and fled.  The truck, a specialized 2000 red Chevy, is marked with “Pennsylvania SPCA” and phone numbers on it.

The SPCA says it is cooperating with the investigation and declined further comment.

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Reported by Pat Loeb, KYW Newsradio 1060.