A number of people are believed to have been injured after an incident at a military training base in West Wales.
It follows reports of an incident at Castlemartin Ranges in Pembrokeshire on Wednesday.
A spokeswoman for the Ministry of Defence: “We are aware of an incident at Castlemartin Ranges. This is still being investigated and therefore it would be inappropriate to comment further.”
Live firing was due to take place on the range from Monday to Friday, with night firing expected on Tuesday and Thursday.
A notice on the Government's website said the road from Bosherston to St Govan's Chapel and the footpath from St Govan's Head to Broadhaven would be closed every day.
Castlemartin, which has been under military control since the 1930s, is the only remaining UK Army range available for armoured units for direct-fire live gunnery exercises.