The emergency services, structural engineers from Calderdale Council,the gas board, electricity board and emergency engineers were called out to Elland Bridge after midnight as the road surface began to sink.
A West Yorkshire Fire and Rescue spokesman said fire crews dealt with a gas leak at the scene and evacuated the Barge and Barrel pub and nearby apartments as a precaution.
The electrity board then worked to isolate the power and crews were on stand by in case of a fire.
A West Yorkshire Police spokesperson said: “Officers are currently dealing with reports of the road surface sinking on Elland Bridge in Elland.
“As a consequence the road is closed and will likely remain so for the foreseeable future.
“This is an evolving incident, we are asking people to please avoid the area if travelling and not to attend the immediate area to watch.
“Appropriate continued assessments are taking place and, where required, occupants of some properties have been asked to leave as a precautionary measure.”
The bridge is now closed in both directions. The area has been affected by flooding in recent days.