Stone Age people in Belgium were hunting with spear-throwers more than 30,000 years ago — the earliest known evidence of such a weapon in Europe, a new study suggests.

After investigating more than 300 previously known flint artifacts found at the Maisières-Canal archaeological site in southern Belgium, a research team documented that 17 have minuscule fractures that indicate they were points for projectiles of some type.

“My conviction is that all of them are from spear-throwers,” study first author Justin Coppe, an archaeologist at the University of Liège in Belgium, told Live Science.

According to the study, the flint points from the Maisières-Canal site, near the town of Mons and the Haine river, show that prehistoric people were hunting there with spear-throwers between 28,000 and 31,000 years ago; and that they apparently preferred these to other types of projectile weapons, such as thrown spears (javelins) and bows and arrows, he said.