Just after dawn in a secluded Cornish harbour, a member of the public reports seeing a tiny boat unload an unusual cargo into a waiting van. Police are soon in pursuit and make a shocking discovery.

The incident was captured by cameras for Channel 4’s hit series Call the Cops, the second series of which airs at 9pm tonight.

The series follows the exploits of Devon and Cornwall Police officers on the beat around both counties, which make up the largest geographical region covered by any force in the country.

Tonight's show follows a shocking case which eventually saw four men jailed for conspiring to smuggle 29 illegal immigrants, including 17 children, into Newlyn harbour on a dilapidated yacht, before cramming them into the back of a van.

The episode begins with a call to police at around 7am on Friday, April 12, 2019. A witness reports what appeared to be a group of foreign nationals getting off a boat at Newlyn.

They were seen walking along a pontoon, onto a footbridge and jumping over a wall to reach the harbour car park, where a white rental van was waiting for them.

Footage of the van with Jon Ransom standing beside it

A dialogue ensues between the police control centre, where officers are searching Cornwall’s network of traffic cameras, and police units on the ground, who are told to look out for the vehicles on the roads.

“Devon and Cornwall is renowned for smuggling, we’ve got so many little coves,” radio dispatch officer Sian tells the programme. “It’s probably easier to slip under the radar if you’re up to no good.”

Officers sent to Newlyn scour through CCTV footage, and are able to obtain the number plate of the van, which was being followed by a blue Audi TT Sport car.

The Audi following the van in Newlyn

The van and Audi are spotted on cameras near Launceston, and 30 police units - nearly a quarter of the response officers on shift - are ordered to intercept the convoy.

Meanwhile, the control room also has to deal with 100 other reported incidents across the two counties.

It is then revealed that two men, Glen Bennett and Frank Walling, both from Lancashire, have been arrested at Newlyn, where they decided to have some breakfast at the harbour café having sailed across the channel.

Officers then search the yacht, which is cramped and in a poor condition.

Inside the cramped yacht

One officer is heard saying: “There is clearly evidence of people sleeping everywhere, proper f***ing grim. You can just smell there’s been a sh*tload of people on here.”

On the ground, the first response unit catches up with the van in Devon, while Sergeant Olly Tayler orders a police helicopter to be sent into the skies to assist the operation.

Sergeant Tayler asks units not to intercept the convoy until an appropriate location beside the M5 is found.

The convoy on the M5 hard shoulder

But then, without warning, the convoy makes a sudden diversion, stopping on the hard shoulder on the M5 near Cullompton.

Two men, Keith Plummer and Jon Ransom, both from Kent, are arrested.

The convoy on the hard shoulder of the M5

Speaking to officers beside the M5, Ransom tells police: “I really haven’t got involved in anything like that [human trafficking] at all, I don’t know why you’re saying that.

“So what have I been arrested actually for? Can you tell me what I’ve done? There seems to be a lot of police officers here for me.”

One of the smugglers being arrested on the side of the M5

It is decided that it is unsafe to open the back of the van beside the M5, and it is driven to nearby Cullompton services.

Sergeant Tayler receives information that those in the back of the van will be treated as victims.

When police officers open the rear van shutter at nearby Cullompton services, they discover 29 illegal immigrants including women and children crammed inside.

Opening the back of the van at Cullompton services

Sergeant Tayler tells them: “Police, stay exactly where you are guys. Stay there, you’re all safe.”

One of the group confirms to police that they are from Vietnam.

The illegal immigrants in the van

“You’ve no idea what experiences they’ve had, none whatsoever,” Sergeant Tayler tells the programme. “You’re merely faced with 29 terrified individuals who have no idea where they are, where they are going or what’s going to happen to them.

“I can’t even begin to imagine what that journey must have been like and the conditions they have endured, how horrific that must be.”

Sergeant Olly Tayler informing officers the immigrants will be treated as victims

The immigrants are given water, and then transported via minibus to a community centre at Chudleigh.

One of the immigrants tells officers that they haven’t eaten for five days, and that they left Vietnam a year ago.

“These people often end up in car washes, takeaways, nail bars, in brothels as sex trade workers, and it just makes me angry that people out there are more than happy to do that at the expense of someone’s absolute misery,” Sergeant Tayler tells the programme.

While Frank Walling reads a prepared statement in police interview, the other three men provide no comment.

Keith Plummer in police interview

All four men were sentenced for their part in the operation at Truro Crown Court in February this year.

Glen Bennett, Frank Walling and Keith Plummer pleaded guilty to assisting unlawful immigration to an EU country in May 2019.

Frank Walling, top left, Glen Bennett, top right, Keith Plummer, bottom left, Jon Ransom, bottom right

Jon Ransom was found guilty of the same charge by a jury following a trial at Truro in October 2019.

Bennett, Walling and Ransom were all jailed for four and a half years each, while Plummer received a sentence of 40 months.

Sentencing the four men, Judge Robert Linford told them: “The yacht contained 29 men, woman and children of Vietnamese origin who were being unlawfully brought into this country.

"They were shepherded into a shuttered van. Those poor people were found crammed in the back sitting on the floor.

“You four are all responsible for the fact that these people are now unlawfully in this country. More than that, you were in a trade which exploited these poor, hapless people. No matter how you dress it up, this was serious and organised crime.

"In the van, being carted around like freight were 29 living, breathing and desperate human beings, for whose plight you cared not one jot.

"This was motivated by gain in the case of each of you, prepared to trade in human misery.

"This is far too serious for anything other than immediate custodial sentences."