The Northern and Newcastle & Central Coast lines are partially closed between Epping and Hornsby, in that direction only due to a train with mechanical problems near Pennant Hills. A train service is operating back and forth between Chatswood and Epping. Trains that normally operate to Hornsby via Macquarie Park are now operating to Hornsby via Pymble. Buses are being organised to operate a replacement service but are yet to arrive. Passengers are advised to delay their journey or allow plenty of extra travel time. Passengers are able to use their train ticket on HillsBus and Transdev services in the area. Trains on the Northern and Newcastle & Central Coast lines towards the Sydney CBD are still operating. Passengers travelling to Hornsby can travel on the Northern Line via Macquarie Park and change at Chatswood for a train to Hornsby on the North Shore Line. Passengers should listen to station announcements and check indicator boards.