The British Army had to stop a firing exercise on the Kent coast as migrants in a boat landed nearby.
Soldiers using live rounds at Lydd Ranges yesterday were ordered to pause shooting after a small boat was seen heading towards a "danger area".
The range is a few miles from Lydd Airport, which has hosted the Army's Watchkeeper drone.
The unmanned air system, previously used in Afghanistan, was brought in to fly over the English Channel to monitor migrant boats.
The migrants' crossing came despite recent high winds in the English Channel that have rendered journeys in dinghies increasingly difficult.
The incident began during a live-firing exercise at Lydd Ranges, when a lookout spotted a boat drawing near.
The vessel was seen moving towards the Range Danger Area and safety concerns were raised, leading to the exercise being paused.
Police, coastguard and Border Force officials were informed of the situation and were later seen arriving at the firing range.
A mix of regular and reserve soldiers were at the military site on Wednesday.
Firing resumed about two hours later.
Dan O'Mahoney, the Home Office's Clandestine Channel Threat Commander, said: "Despite very poor weather in the Channel yesterday, a small boat managed to make this perilous crossing, underlining the extreme danger people smugglers are willing to expose people to for profit."
More than 7,000 migrants have crossed to the UK aboard small boats in 2020, according to the Press Association.
Lydd Ranges is a military site located south of the Kent town of Lydd.
It carries the Government warning: "If the red flags and/or lights are hoisted, regardless of the timings, do not enter the training area.
"This is a danger to life."
Cover image: The entrance to the Lydd ranges, pictured in 2006 (Picture: PA).