According to traffic reports, an air ambulance landed at the scene of a serious crash involving a car and a bike in East Sussex. A259 East Dean Road is closed eastbound after the collision on Gilberts Drive. The road remains closed hours after the collision, due to investigation work by the emergency services. Slow traffic has been reported in the area. There have also been reports of a crash in Brighton. According to traffic reports, a car has been involved in a collision with a parked vehicle on Colbourne Avenue near Hillside. Traffic is said to be coping well. In Newhaven, there is slow traffic on A259 westbound at Newhaven Swing Bridge. In West Sussex, a vehicle has stalled on the M23 near Gatwick Airport (Junction 9). Traffic is reportedly coping well southbound after the incident. In Billingshurst, A29 Stane Street is reportedly partly blocked both ways due to an accident around Okehurst Lane. Meanwhile, on the railway in Sussex, ‘multiple incidents’, along with the ‘severe hot weather across the network’, are affecting train services. Southern Rail said a reduced service is in operation with ‘some stations not being served’. A spokesperson added: “Services between Brighton and Lewes are being disrupted due to a problem with electricity supply. “Both lines are now blocked between Lewes and Brighton so no services are able to run. “You will need to use an alternative route to complete your journey.” People are being asked to only travel by train if ‘absolutely essential’ after a weather warning for extreme heat was issued by Met Office. Southern said people should 'avoid beach trips by train ‘as these are not essential’. Have you read?: A27: Worthing driver caught speeding at more than 140mph Gatwick Airport: All the cancelled and delayed easyJet, British Airways, Vueling and Wizz Air flights for Monday, July 18 UK heatwave: This is when thunder and rain will break 'extreme heat' in Sussex For the latest breaking news where you live in Sussex, follow us on Twitter and on Facebook.