First Minister Nicola Sturgeon admitted that Scotrail passengers were owed an apology as she was grilled over the rail network's failings at First Minister's Questions.

Conservative Deputy Leader, Jackson Carlaw raised the issue of the performance of Scotland's railway operator, Scotrail.

He said: "We've got new official figures that show that since 2011 there have in fact been more than 35,000 cancellations or part cancellations caused entirely by ScotRail, that amounts to some 5,000 a year.

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"People want to know why this SNP Government is failing to deliver."

He added: "Punctuality on our train service reaching its worst point for 12 years, hundreds of trains cancelled and shortages of staff because people are being trained to use the new class of trains which are also delayed, causing another 100 services to be cut last month.

"Doesn't the First Minister think train passengers across Scotland are owed an apology?"

The First Minister agreed passengers are owed an apology.

She said: "We've seen a significant and unacceptable number of delays that are clearly the responsibility of ScotRail.

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"I can report to parliament that cancellations of this type have fallen as the week has progressed from around 144 on Monday to an estimated 40 today.

"Progress is being made but it is not good enough - we expect, indeed we demand, better from the rail operator and the Transport Secretary continues to work closely with them to ensure that we continue to see improvements in the days to come."

She said the overall level of cancellations this week were due to a number of factors, not all the responsibility of ScotRail, including infrastructure issues such as signal failures and train crew shortages.