A CN signal malfunction near the Mimico station caused some delays for GO Transit commuters during Monday's afternoon rush-hour.

At first GO Transit warned of major delays, but later downgraded the warning, stating that the problem had not been resolved but the situation was improving.

A report posted on the website just before rush-hour advised commuters to expect delays of up to 15 minutes.

Several rush-hour trains were cancelled, including a 4:10 train to Burlington and a 5:33 trip to Pickering.

There were also several cancelled train trips during the early afternoon on the Lakeshore Line.

The CN signal glitch meant trains running on the westbound Lakeshore Line had to be manually switched, a time-consuming process.

It was the second problem to plague GO Transit Monday — with an early morning accident at Highway 407 and Bramalea Road causing delays for westbound GO buses. There were no major disruptions from the accident.