A boy of eight was taken to hospital after sinking waist-deep in a marshy bog.
Firefighters pulled the boy to safety after he got trapped walking across a field with a young girl.
The youngster, who has not been named, was taken to Eastbourne District General Hospital, where he was treated for hypothermia.
The alarm was raised shortly after 6.20pm on Saturday when the fire brigade received reports of a child trapped up to his knees on land next to the new link road at Willingdon Drove, Eastbourne.
Two fire crews from Eastbourne arrived to find the youngster had already sunk to waist level.
Assistant divisional officer Dick Ashley said: "A specialist crew was on its way from Crowborough with an inflatable rescue path but officers rescued him with a tug and a pull before it arrived.
"It was very dark and, although we're not medics, we suspected something like hypothermia was setting in.
"The officers waded through the mud but weren't in any danger because they took it very carefully and steadily.
"They were in a bit of a state when they were finished though - very wet and muddy."
The fire brigade said people should always be aware of the ground they were walking on and avoid areas known to be marshy, particularly with icy weather coming up.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article