Rail commuters have been warned to expect delays and cancellations because of a points failure near Bolton.
Following the late completion of maintenance work, a problem with the points at Lostock was uncovered.
Engineers have been sent to fix the problem.
Network Rail has apologised and warned commuters to expect delays and cancellations.
Manchester Piccadilly (@networkrailMAN) tweeted: "Delays & cancellations through #Bolton
"This is due to issues with a set of points (equipment that allows trains to move from one track to another) near #Lostock
"Really sorry to passengers impacted this morning.our engineers are on site fixing the points issue near #Lostock
"The problem was found early this morning after track maintenance work was finished later than planned. We’re working to get this fixed ASAP."
Northern tweeted: "Due to engineering works not being finished on time at Bolton the line is blocked. Network Rail are trying to finish up as soon as they can, sorry for the wait."
