Scottish teachers have taken almost 500,000 days off for mental health reasons in the last three years, according to new figures obtained by the Scottish Liberal Democrats.

A freedom of information request by the party showed teachers, headteachers, teaching support staff and nursery staff employed by councils have been off for 477,000 days due to mental health issues since 2013/14.

The figures show a year-on-year rise, with 158,639 days in 2015/16 compared with more than 150,000 in 2014/15 and almost 140,000 in 2013/14.

The Lib Dems said the data highlights the need to reduce the burden on teachers, who have complained about heavy workloads in recent years, and deliver mental health treatment when people need it.

Health spokesman Alex Cole-Hamilton said: "The fact teachers have taken nearly half a million days off work due to mental ill health paints a very worrying picture of a workforce that is under severe strain.

"The fact that numbers are rising year-on-year shows they are clearly not receiving the right support. It raises serious questions about the Scottish Government's education and mental health policies.

"Scottish Liberal Democrats have consistently made the case for taking mental health funding and support to record levels.

"We know mental health treatment isn't available when people need it. Tens of thousands of people have waited longer than 18 weeks for the help they need.

"We have also called for a penny for education, raising £500m that would fund extra support for both teachers and pupils, transform Scottish education and reverse our declining international standing."

A Scottish Government spokeswoman said: "We continue to work closely with unions and local authorities to address issues facing teachers and ensure they are properly supported.

"We recognise the crucial role that mental health plays, particularly in the work place.

"It's why we are the first Scottish Government to have a ministerial post dedicated to mental health and why we are investing an additional £150m to boost support for areas which are absolute priorities for us, including improving access to services, and increasing support for early intervention and prevention, to support people to keep well.

"This will deliver the transformation in mental health services we want to achieve over the next 10 years.

"We will set out our vision for transformation in the next Mental Health Strategy due for publication in early 2017."