Archaeologists excavating the ruins of Chan Chan, which served as the capital of the Chimú Empire in what’s now northern Peru until the 15th century, have discovered a mass grave containing the remains of around 25 people.

Jorge Meneses, an archaeologist at Trujillo National University who is leading the research project, tells the Andina news agency that the team discovered the burial in a raised area of the Great Chimú walled complex.

“Most of them belonged to women under 30 who were buried with objects used in textile activities, [as well as] a couple of children and a couple of teenagers,” he says.

One of the skeletons was apparently buried at the site shortly after death. Other bones were mixed together and bleached by the elements, suggesting they were moved there later, BBC News reports. The remains were wrapped in layers of material, first in a cotton fabric and then in a wrapping made of plant tissue.

Some of the women’s bodies were placed in a seated position with their legs bent and needles, chalk and sewing tools placed beside them. This arrangement may have been a recreation of activities the women engaged in when they were alive, says Peru’s Ministry of Culture in a statement.

Researchers also found dozens of ceramic vessels in the grave. Sinthya Cueva, head of the Chan Chan Archaeological Research Program, tells Adina that the wealth of grave goods suggests the people buried there were elite members of society.