Sark's government says it is responding to an ongoing incident believed to be a fire in an area of undergrowth near the island's abandoned silver mines.
The extent of the blaze is not yet known.
Several hamlets are nearby - while there has been no indication they are under immediate threat, reports suggest some residents are being evacuated.
Sark Fire and Rescue Service is understood to be receiving assistance from crews from Guernsey.
The incident comes a day after Guernsey's Chief Fire Officer urged people to take extra care in the current tinder-dry conditions, warning that even small sparks could quickly lead to fires.
@islandfm Crews from Sark and Guernsey have been working to tackle a major blaze in Little Sark. (10.7.26) Videos from Andrew Cook #channelislands #fire ♬ original sound - Island FM
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