GO Transit says its Barrie trains are stopping at York University again following a freight train derailment.

Trans were bypassing the York University stop for part of the morning commute, so passengers had to transfer to GO shuttle buses at the Rutherford GO Station until the problem was cleared at about 8 a.m.

CN Rail spokeswoman Lindsay Fedchyshyn said a minor derailment occurred in Markham on Sunday at about 11:15 p.m.

Two rail cars containing steel manufacturing pieces derailed, but there were no injuries or environmental concerns, Fedchyshyn told CP24.

Freight trains were diverted onto a rail line that runs through Barrie, and that was responsible for disrupting GO train service, Fedchyshyn said.

Once trains were diverted, one of the freight trains came into contact with some hanging overhead wires, causing further delays, Fedchyshyn said.

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