Gardaí have carried out searches at four premises in the Roscahill area of Oughterard in Co. Galway in relation to the arson attack at Ross Lake House Hotel on 16 December.
A number of items were seized during these searches, and they will be subject to analysis which will determine the next stages of the investigation.
An incident room is in place in relation to this large scale investigation which has resulted in 229 investigative tasks being conducted and 145 statements taken to date.
The investigation team thanked the local community for their support to date and are appealing for anyone who may have information regarding this incident to contact them.
In particular, members of the community in the Roscahill, Outhterard and surrounding areas who may be able to assist Gardaí are asked to come forward.
Gardaí can be contacted at Clifden Garda Station on 095 22500, the Garda Confidential Line on 1800 666 111, or any Garda Station.
All information received will be treated in a confidential and sensitive manner.
