Fr Martin Newell of the London Catholic Worker community was sentenced to 24 days imprisonment yesterday (Friday) at Highbury Magistrates Court.
Newell was brought before the court for refusing to pay a fine arising from cutting into the Northwood Headquarters in December 2008.
The anti-war direct action was timed for the "Feast of the Holy Innocents" on the Catholic liturgical calender.
From the dock Fr Newell said: "I work with refugees from Iraq and Afghanistan at the Catholic Worker. I am opposed to the wars we have been waging on these countries. I have nonviolently resisted these wars since they began. I'm refusing to pay this fine as a form of further non-cooperation with these wars."
Northwood Headquarters is the command centre for British forces deployed overseas. The base has been the location of a number of nonviolent direct actions by the pacifist Catholic Worker community over the past decade.