A road has partially reopened following a serious crash that caused gridlock in Maidstone.

A car and a motorbike collided on the A20 London Road earlier this afternoon, leading to the road being closed from the Terrace Road entrance to the bottom of London Road.

The 20-year-old man who was riding the motorbike suffered serious injuries.

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Following hours of congestion in and around the town, Kent Highways announced just after 6pm that one lane of London Road had been reopened.

A spokesman said the open lane was for traffic coming from the A26 Tonbridge Road. Vehicles travelling southbound on the A20 are still being diverted down Buckland Hill, the spokesman added.

The accident was reported shortly before 2pm outside Formula One Autocentre.

Traffic around the town is delayed and motorists are still being advised to avoid the area if possible and to expect delays.

A South East Coast Ambulance Service spokesman said: "At 1.45pm we attended a collision between a car and motorcycle at Tonbridge Road, Maidstone.

"The 20-year-old male motorcyclist suffered serious injuries and was attended by paramedics and the Air Ambulance doctor who arrived by vehicle.

"The road is likely to be closed for several hours."

Arriva Kent said all Maidstone bus services are currently delayed.

VIDEO: Serious crash closes road in Maidstone

Six buses are caught up in the gridlock, with vehicles being diverted along Buckland Road and drivers heading to Allington and Aylesford advised to head to the M20 and come off at junction 5.

Nu-Venture has confirmed services 22, 58, 78 and 88 are being diverted and are not serving London Road.

Kent, Surrey and Sussex Air Ambulance received a call at 1.56pm and sent a road crew to the scene.

Several police vehicles rushed to the scene alongside paramedics, crash investigators and more than a dozen officers.

Customers are unable to access several businesses on the road, including Majestic Wines and Formula One Autocentre.

Areas including Allington and Barming are reported as gridlocked because of the incident, with traffic at a standstill on busy roads such as Hermitage Lane and Queens Road.

People are using East Farleigh bridge as a diversion which is also congested.

Once out of Maidstone, drivers heading north, towards Sittingbourne, the Isle of Sheppey or junction 5 of the M2, face further delays as part of the A249 is closed due to a burst water main.

Anyone who witnessed the Maidstone collision is urged to call 01622 798538 quoting reference 15-0632. Alternatively email sciu.td@kent.pnn.police.uk.