PITTSBURGH — A union leader is taking issue with a Western Pennsylvania transit agency’s contention that two bus drivers may have been engaging in reckless behavior before one of them crashed.

The Port Authority of Allegheny County says video appears to show the drivers gesturing at each other moments before one bus crashed through a guide rail.

Agency spokesman Jim Ritchie said the drivers could be fired if investigators confirm their behavior caused the crash.

Stephen Palonis, president of Local 85 of the Amalgamated Transit Union, said he saw no reckless driving and thinks the drivers waved to each other.