LISBON, Portugal (AP) — Portuguese researchers suspect that a dozen skeletons found in an ancient garbage dump were Jewish victims of the Inquisition more than 400 years ago.

The excavation team found the remains at what was called the Jail Cleaning Yard of the Inquisition Court in Evora, 135 kilometers (84 miles) east of the Portuguese capital, Lisbon. The dump was in use roughly between 1568 and 1634.

The three male and nine female bodies "were discarded into the dump like household garbage," with no funeral structures nor grave goods, and the skeletons were lying skewed on the ground, the researchers said in the September edition of the Journal of Anthropological Archaeology, provided to The Associated Press on Wednesday.

The Portuguese Inquisition was established in 1536. Its most common accusation was maintaining outlawed Jewish practices in secret. Hundreds of Jews were burned at the stake, and living conditions in Inquisition jails often caused prisoners' deaths. A proper burial was denied to Jews.

The researchers said it was impossible to know for certain if the skeletons were Jews.

The excavations were carried out in 2007 and 2008 during the renovation of the former Inquisition court building. Only 12 percent of the yard was excavated, researchers from the Portuguese universities of Evora and Coimbra said.