Dublin Metropolitan Prisoners Books from over 100 years ago containing reports of over 30,000 arrests have been published online.
The reports contain details of prisoners during the Lockout of 1913, the outbreak of the First World War and the 1916 Easter Rising.
These important records, which went missing when the Dublin Metropolitan Police was abolished in 1924, recently came into the possession of SIPTU after being discovered during a house refurbishment.
They contain arrests made between 1905 to 1918.
Over 30,000 people were arrested during that period including James Larkin and James Connolly.
The records state that both Larkin and Connolly were arrested in August 1913 - the offence was incitement to crime.
These files have now been handed over to An Garda Síochána and are available to view online.
Garda Commissioner Nóirín O'Sullivan and SIPTU's Jack O'Connor look at DMP files dating from 1905 to 1918. pic.twitter.com/SbqmgxJ4Xg— Sinéad Hussey (@SineadHus) May 11, 2016