Officers were called to concerns for the welfare of a man on the crossing at around 6am yesterday (March 12).
The incident caused severe three-hour delays on the M25 clockwise approaching the crossing.
The man is now safe and being cared for by healthcare professionals.
The crossing fully re-opened at around 10.30am and all delays have since returned to normal.
A spokesperson for Essex Police said: “The Dartford River Crossing is now open following an incident reported to us at 6am, Tuesday 12 March.
“We were called to concerns for the welfare of a man on the crossing.
“Traffic was held while officers worked at the scene.
“The man is now safe and being cared for by healthcare professionals.
“The crossing was fully re-opened at 10.30am.”
