Nine people were found murdered Monday at a luxurious country home near the northwestern city of Medellin, Colombian police said.

"It could be a settling of scores," the Medellin police chief, Gen. Yesid Vazquez, told Efe from the crime scene at the La Piscina estate in the municipality of Envigado.

All of the victims - five men and four women - were shot in the head.

Police found an armor-plated SUV, a motorcycle and a gun just outside the home.

Investigators are still trying to determine whether the shooters forced their way into the home or were among the guests at what appears to have been a weekend-long party at the residence.

The home "was recently sold by a lady from Envigado," Gen. Vazquez said, though adding that police have yet to identify the victims of "this massacre."

La Piscina lies near what used to be La Catedral, the luxury prison drug lord Pablo Escobar had built for himself in 1991 when he agreed to surrender in exchange for the government's promise not to extradite him to the United States.

Escobar spent a little more than a year in the prison before fleeing, only to be tracked down and killed in Medellin in 1993.

The prison was later converted to a retirement home for low-income people. EFE