Scotland's chief constable Sir Stephen House is spending his last day in the job after 35 years in policing.

He had been due to stand down at the end of his contract in September 2016 but he announced in August that he would go early.

His departure follows a series of high-profile incidents which saw the police chief come under growing pressure and face calls to resign.

Sir Stephen was selected to head the new single force in 2012 after notching up three decades of service at six UK forces, including as chief constable of Strathclyde Police.

He was credited for the successful policing of last year's Commonwealth Games, but he faced criticism for his decision to put armed officers on routine patrols and the force's large-scale use of consensual stop-and-search.

The death of Sheku Bayoh in police custody put additional pressure on officers, with an investigation by the Police Investigations and Review Commissioner ongoing.

Dissatisfaction came to a head in the wave of shock after the deaths of Lamara Bell, 25, and her partner John Yuill, 28, in July.

It emerged it had taken three days for officers to respond to reports of their car going off the M9 near Stirling after a call from a member of the public.

Sir Stephen issued an unprecedented apology to the couple's families.

A history and English literature graduate, he spent the early part of his career at Sussex Police before going on to serve with Northamptonshire, West Yorkshire and Staffordshire forces.

He was appointed deputy assistant commissioner at the Metropolitan Police in December 2001 and five years later took on the role of assistant commissioner with a responsibility for homicide, gun crime and fraud.

Sir Stephen grew up in Glasgow and moved his family to the city to head what was then Scotland's largest force in 2007.

As Police Scotland chief constable, he was responsible for leading the transition to the single service, amalgamating eight police forces, which came into effect on April 1 2013.

He was included in the Queen's Birthday Honours list that year, earning a knighthood for his services to law and order. He was previously awarded the Queen's Police Medal in 2005.

Deputy Chief Constable Neil Richardson will take over as acting chief constable until Sir Stephen's successor is appointed.