ScotRail confirmed on social media that services between Glasgow and Barrhead / Kilmarnock / Carlisle have been disrupted.
This is because of a signalling fault at Kilmarnock.
ScotRail posted: “Due to a fault with the signalling system at Kilmarnock, trains between Glasgow and Barrhead / Kilmarnock / Carlisle will be disrupted. @NetworkRailSCOT are on site and are working to rectify the issue as soon as possible.”