More on KentOnline
The M25 has reopened after a recovery driver was hit and killed by a lorry.
The incident happened on the anticlockwise side between junction 5 for the M26 and 4 for Orpington at around 6.15am.
Emergency services closed the carriageway for several hours, but all lanes had reopened by 2pm.
Earlier, Kent Police's roads unit tweeted to say the road is likely to be closed for some time.
A police spokesman said: "The M25 is currently closed between Junctions 5 and 4 anti-clockwise following a serious collision.
"Kent Police was notified of the incident involving two heavy goods vehicles at 6.17am on Friday 22 September 2017 and officers are currently at the scene.
"The hard shoulder and lane one are expected to be closed for several hours while initial enquiries are carried out.
"It is hoped that lanes two and three can be reopened earlier to help ease traffic congestion."
A second crash in the queues also added to delays
A lorry and a car collided just before junction 5 on the anticlockwise side at around 10.30am, causing the car to spin and come to a stop across lanes three and four.
Highways held traffic until just before midday.
The A21 north-bound at Sevenoaks was also closed causing slow traffic between the A25 at Westerham and junction 5 of the M25.
A spokesman added: "Road users are advised to allow extra time to complete their journeys or to seek an alternative route if possible."
Listen to kmfm for the latest travel updates.