LOWER MERION, Pa. (CBS) – An accident involving a tractor trailer and an overturned dump truck closed the eastbound lanes of the Schuylkill Expressway near the Conshohocken Curve for several hours Tuesday.

The six-vehicle crash happened at about 11:30 a.m. along I-76 eastbound between the Conshohocken exit and the Gladwyne exit.

Drivers were urged to use alternate routes as the roadway remained closed for more than four hours while crews work to upright the dump truck which lost a load of rocks. Haz-mat crews were also brought in to clean up fuel spills from both vehicles.

Amazingly, no injuries were reported.

The backlog has been cleared of all passenger-sized cars by 3 p.m., but larger vehicles remained because they couldn’t be turned around easily.

By 4 p.m. all eastbound lanes were finally reopened.

The cause of the crash is under investigation.

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