Archeologists have discovered what might be the biggest single mass child sacrifice event in human history.
Uncovered near modern-day Trujillo in northern Peru, the mass grave has over 140 child skeletons believed to be sacrificed at the same time at some point, 550 years ago, during the Chimú civilization.
Alongside the grisly finds are an additional 200 llama skeletons - all aged around 18 months and buried facing east towards the Andes Mountains - that are believed to be involved in the same mass sacrifice.
The find was supported by grants from the National Geographic Society after an other huge field of sacrifices - 40 human and 72 llama - was discovered during the excavation of a 3,500 year old temple back in 2011.
Gabriel Prieto, one of the lead researcher, said: "When people hear about what happened and the scale of it, the first thing they always ask is why."
The excavation has a few clues - notably, a layer of mud in which the victims were buried could have been caused by "severe rain and flooding" in the usually dry area - possibly caused by an extreme weather event such as El Niño. This kind of flooding could have "disrupted marine fisheries in the area, while coastal flooding could have overwhelmed the Chimú's extensive infrastructure of agricultural canals," National Geographic reports.
The children's sacrifice may have been an extreme measure when adult sacrifice failed to calm the weather.
"People sacrifice that which is of most and greatest value to them," bioarchaeologist Haagen Klaus told National Geographic. "They may have seen that [adult sacrifice] was ineffective. The rains kept coming. Maybe there was a need for a new type of sacrificial victim."