Rural villages many miles from the coast are under threat from illegal migrant boats which have sailed up Britain's waterways.
On Monday, the National Crime Agency (NCA) and Border Force officers arrested five men after a yacht carrying seven illegal Albanian migrants was intercepted nearly five nautical miles inland from the south coast in Chichester Marina, West Sussex.
Two crew members, one a British national aged 42 and another aged 25, were arrested on suspicion of facilitating illegal immigration to the UK.
Three more people, a British national aged 38, and two Albanians aged 24 and 32, were suspected of being a "shore party" to meet the yacht.
They were both arrested on suspicion of people smuggling offences, with the seven Albanians taken to immigration detention.
Home Office intelligence estimates there are up to 9,000 locations where boats could be landed by gangs seeking to bring migrants, drugs, and other contraband into the country.
Villages as far inland as 35 miles have been instructed to watch out for illegal migrant boats.
Airmyn, a Yorkshire village on the banks of the River Aire, has had signs posted which read: "Boats arriving at unusual times? Report it Let's sort it."
PICTURED: This yacht carrying Albanian migrants was intercepted by authorities as it arrived in Chichester Marina, West Sussex
|NATIONAL CRIME AGENCY
The notice, which features a backdrop of a yacht approaching a shoreline, gives details of how to contact UK Border Watch via Crimestoppers.
The 800-person village has been targeted as part of the Home Office-backed Operation Kraken to report "suspicious" and "strange" maritime behaviour.
Tony Smith, the former director general of the Border Force, said illegal maritime entries were more likely to be linked to organised crime than small boat migrants.
He told The Telegraph: "It is more likely to be serious organised crime as opposed to opportunistic illegal migrants.
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This post advertises spots on a yacht headed towards the UK
|TIKTOK
"These are people who have got money. This has always been a risk with the length of coastline we have.
"You cannot put a Border Force officer in every little harbour and monitor every beach and inlet."
On TikTok, accounts seeming to be run by people smugglers have advertised yacht trips to the UK.
One post, which showed a luxury yacht, said: "We're resuming the yacht to the UK this weekend."
Alex Norris said the Home Office will use 'all powers at our disposal' to tackle people smuggling gangs
| PAAnother said: "Who is in Belgium? The yacht will be back tomorrow morning. Safe passage through the checkpoints."
People smuggling is a lucrative business, with migrants charged five-figure sums to enter the UK, according to Mihnea Cuibus, a researcher at Oxford University's Migration Observatory.
The same account has offered to smuggle people to the UK by plane, with payment required upon arrival in Britain.
Alex Norris, the Home Office minister, said: "Make no mistake - we will use all powers at our disposal to take action against those seeking to smuggle people into the UK.
"Smuggling gangs should be under no illusion that no matter the method they use, we will root them out and ensure they face the full force of the law."