Later update: The road was re-opened at 1.42pm on August 7.
The A158 between Bunkers Hill roundabout in Lincoln and Sudbrooke is likely to be closed for the rest of the day due to a gas leak, police said.
The roads policing unit advised drivers to find alternative routes through Sudbrooke.
The leak was first reported at around 9.25am on Thursday, August 7.
The road closure is likely to be in place for the rest of the day and diversions have been put in place.
Lincolnshire Police said: “All efforts will be made by the relevant agencies to safely re-open the road as soon as possible.”