A half-dozen Wentzville businesses had to be temporarily closed Thursday after their employees were evacuated because of an underground gas leak. 

Authorities say that shortly before 10 a.m. contractors working on a road widening project in the four-hundred block of Old Business 61 accidentally ruptured a gas line while removing an old line.  The gas leaked into an abandoned underground pipe causing a minor explosion.  The gas was quickly contained, but the employees had to wait until it dissipated before returning to work.