Police have closed off a rural area in Co Londonderry used for Army reservist training after a warning of an explosive device being left there.
On Wednesday the security alert was centred on the Drumsurn area near Dungiven.
An anonymous telephone caller to a charity in the early hours of Wednesday - speaking with and Irish accent and claiming to be from “the Republican Movement” - said a device had been lying undiscovered for several days at Belraugh Road off the Legavallon Road.
The area where the device is reported to have been left is a mountainous, forest area outside the village of Drumsurn and is sparsely populated.
A police spokesman said it was important that local people remained vigilant and rang 999 if they discover any suspicious objects.
Dungiven Sinn Fein councillor Sean McGlinchey criticised police for causing “worry” by releasing what he called “such vague” information.
In response to a complaint from another Sinn Fein councillor last month, the Ministry of Defence confirmed reservists from 38 (Irish) Brigade were involved in “essential training” in the area.
A spokesperson said: “This training ensures that the reservists, drawn from across the community, are ready for any commitments including humanitarian aid....to combat Ebola in western Africa”.