KINGWOOD, Texas - Union Pacific engineers are working to stop a train bridge from sinking.

The bridge goes over the San Jacinto River and according to the railroad, a Union Pacific train that was 73 cars long was going south on the tracks when the train hit a low spot was a couple of the cars became uncoupled.

Union Pacific says as a safety mechanism, the train went into an emergency stop. The conductor got out and noticed the issue. Crews were able to pull the cars off the tracks and they have all been cleared.

The train was heading to Houston and was not carrying anything.

Union Pacific estimates it will take 72 hours to fix the problem.