Sydney Trains released CCTV footage on Monday, July 23, of a child in school uniform crossing the yellow line at Thornleigh Station; the child had run forward to pick up something he’d dropped, causing him to come within inches of an oncoming train.

They posted the footage as a warning to children who take public transport to school, sending out the reminder before kids returned to school across New South Wales on Tuesday.

“This young man almost found out the the hard way, just how quickly things can go wrong,” they wrote. “Always pay attention to your surroundings, and stay behind that yellow line!” Credit: Sydney Trains via Storyful