THESSALONIKI (AP) — Police in northwestern Greece say that unknown individuals have removed more than 100 border markers over a section of the frontier between Greece and its northern neighbor of FYROM.

Police in the city of Florina said Sunday that 105 concrete markers, some of them pyramids about a meter (more than three feet) tall and some smaller cylinders, were reportedly removed between Thursday and Friday along a 13-kilometer (eight-mile) section of the border. The incident is under investigation.

Last July, Greece and FYROM reached an agreement settling a 27-year-old dispute over FYROM’s name that would rename Greece’s northern neighbor “Northern Macedonia” to clearly distinguish it from the Greek province of Macedonia. The agreement must still be ratified by both countries.