Members of the Shell to Sea campaign began an all-night candelit vigil at the Corrib gas refinery gates in north Mayo last night to mark a year since deployment of extra gardaí to the area.
Up to 200 gardaí have been deployed during certain periods to provide escorts for employees building the Bellanaboy refinery, since work resumed there last October.
Clashes between gardaí and protestors have taken place on a number of occasions, and the bill for the security has been running at €800,000 a month, according to figures supplied by former minister for justice Michael McDowell last April.
However, gardaí say that their numbers are back at almost normal levels in the Belmullet area.
Shell to Sea spokesman John Monaghan said in a statement yesterday that the vigil from midnight until 6.30am today was being held to mark "the one-year anniversary of the siege of the local community".
A prayer service is due to be held at dawn today ,followed by a "short statement on the ongoing situation".