Milan was last seen on Debora Bakelaan in Heemskerk. He may have left on foot in the direction of Wijkerstraatweg in Velsen-Noord.
The sixteen-year-old is mentally disabled and has difficulty speaking. He is about 1.80-1.90 meters tall and has medium-length brown hair.
The boy was wearing a green camouflage jacket, dark blue sweatpants and black sneakers when he was last seen.
The police ask people who have seen the boy to contact 112.