GLASGOW'S Subway system is in "chaos" as passengers hit out at a fault which renders Smartcards useless.

The Subway gate system is currently not able to read the Smartcards, which are popular among frequent users, forcing staff to hand out single paper tickets.

SPT says it is working to resolve the issue but it is not known what caused the system to go down.

One commuter said: "The Bramble card works well, generally, through station gates but it's slower than basic single cards and the system has never worked as smoothly or across all transport as the Oyster card in London.

"But clearly something has gone very wrong with the expensive Bramble.

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"My guess is either someone cut a line while doing the station upgrades, or the heat is too much for computers. Hopefully they fix it soon."

The issue is understood to have been first reported on Wednesday morning at Cowcaddens but by the evening it had spread to the city's other stations.

A spokeswoman for SPT said: "The Subway gate system is currently not reading Smartcards so paper tickets are being issued to passengers to exit the Subway. "Subway staff are on hand to assist passengers and we are working with our suppliers to rectify the problem as soon as possible.

“We apologise for any inconvenience to passengers. Smartcard holders will not be disadvantaged and should speak to staff for assistance. Subway services are running as normal.”