SAINT JOHN, N.B. -- Four New Brunswick Southern Railway cars carrying gypsum rock derailed at a crossing Monday afternoon in Saint John, N.B.

A spokeswoman for the Irving-owned company said the train was moving gypsum across the Bayside Drive crossing to Atlantic Wallboard when the derailment occurred around 3:30 p.m.

Mary Keith said in an email that the train was moving at about 16 kilometres per hour at the time.

She said nobody was injured, no property was damaged and no hazardous materials were being transported in the railway cars, which remained upright.

The release said an initial investigation of the tracks indicated a rail break may be the cause.

As of 5:15 p.m., one lane of the two-lane road crossing had been cleared, and the railway said it expected normal operations to resume by midnight on Monday.