Strathclyde Police have confirmed that an officer was shot dead this morning at the Baird Street Police Station in Glasgow.
Assistant Chief Constable Bernard Higgins said an investigation into the incident is now underway, and that the officer's name will not be released until the family had been told.
He said: "It is with great sadness that I have to tell you that a serving Strathclyde Police officer died today, Monday, 5 November, in an incident where a firearm was discharged at Baird Street Police Office."
According to Martyn McLaughlin, a senior reporter at the Scotsman newspaper, the officer could have been a firearms officer.
He tweeted: "Station is base for force's firearms unit but unclear whether victim was firearms officer with Strathclyde Police."
Higgins added: "No details of the officer involved will be released until family members have been informed.
"A full investigation into the circumstances is currently underway and a report will be submitted to the Procurator Fiscal. In accordance with ACPO's guidelines, officers from an independent force, Lothian and Borders Police have been appointed to oversee the investigation.
"Our thoughts are with the officer's family and friends at this difficult time."
It is thought that no one else is being sought in relation to the incident