A team of Croatian researchers are training honeybees to sniff out unexploded mines that still pepper the Balkans.

Nikola Kezic, a professor in the Department of Agriculture at Zagreb University, has been exploring using bees to find landmines since 2007. Croatia, Bosnia-Hercegovina, and other countries from former Yugoslavia still have around 250,000 buried mines that were left there during the wars of the early 90s. Since the end of the war, more than 300 people have been killed in Croatia alone by the explosives, including 66 de-miners.

Tracking down the mines can be extremely costly and dangerous. However, by training bees (which are able to detect odors from 4.5 kilometers away) to associate the smell of TNT with sugar, the researchers can create an effective way of identifying the locations of mines.

Kezic leads a multimillion-pound program sponsored by the EU, called Tiramisu, to detect landmines across the continent. His team has been working in a net tent filled with the insects and several feeding posts containing a sugar solution—some of which contain traces of TNT. The bees, which have already been trained to associate food with the smell of TNT, gather mainly at those feeding posts containing TNT. The movements of the bees are tracked from afar using thermal cameras. Bees have the advantage of being extremely small, so they don't run the risk of setting off the explosives in the same way that trained mammals such as dogs or rats do.

The research is similar to experiments conducted by DARPA in the US, where bees were mounted with tiny radio tags so their location could be accurately tracked.

The research is ongoing, but once the team is confident in the bees' landmine-seeking abilities, they will release the creatures in areas that have been de-mined to see whether the field has been successfully swept by humans.

Kezic told AP, "it has been scientifically proven that there are never zero mines on a de-mined field, and that's where bees could come in."

This story originally appeared on Wired UK.