Ahmed from Ahwaz in southwest Iran has lived in a makeshift migrant camp near the Calais dunes for about two months.

Together with his wife, eight-year-old daughter and two-year-old son he boarded an overloaded rubber boat for a night voyage to Britain sometime in November 2018.

The fragile vessel, however, quickly tipped and his children fell into the water, he said.

Eight people helped pull them back aboard and within an hour the boat was back on the beach.

Ahmed said a friend arranged the boat ride but he didn't know which beach the group left from or the exact date.

Ahmed and his family are part of the recent spike in bids by mostly Iranian migrants desperate to get to Britain mainly in rubber boats, as reported by French border officials.

In a bid to end the high-risk tactic, France is combing beaches, dunes and the frigid, murky coastal waters of northern France.

The goal is to save lives in one of the world's busiest, and most treacherous, waterways, known for its strong currents, and to catch smugglers who appear to have found a new money-making niche, adding to their specialty of hiding migrants in freight trucks that cross the Channel on ferries or trains.

The stepped-up security is beginning to pay off. A patrol discovered a motorized rubber boat and four people this week in the dunes south of Calais, a top French border control official told The Associated Press.

French authorities counted 71 small boat crossings or attempts in 2018 - 57 for the months of November and December alone, according to the Interior Ministry.

Forty of the crossings were successful, with the majority of the 504 migrants who tried managing to make it to British waters or the coast.

In 2017, there were only 12 such crossings.

Most migrants in northern France still opt to hide among vegetables or other cargo in trucks, trying to outwit heartbeat detectors, scans and other sophisticated equipment seeking to rout them out at ports in Calais and Dunkirk and at the Eurotunnel.

About 3,000 migrants were discovered hiding in trucks in the region in 2018, Franck Toulliou, the No. 2 Air and Border Police official said.

Toulliou said that fears voiced by some migrants about increased checks with the approach of Brexit are unfounded because nothing will change for those trying to enter Britain illegally.

"In terms of the level of controls (after Brexit), there won't be more or less. We'll check (all vehicles), 100 percent," he said.

The cliffs of Dover, visible in good weather, are irresistible for some of the desperate people huddled around camp fires in hideouts around Calais, in defiance of police who regularly clear them out and a harsh policy of the town that harbored a huge makeshift camp of thousands of migrants.

The camp went up in flames during a dismantling operation in the fall of 2016.

Toulliou said that no Iranian smuggling network has yet been discovered, even though the French dismantled 26 smuggling networks in 2018 along the northern coast.

Britain has pressured France to do more to end the boat crossings, with London injecting funds as it has in the past.

France announced in early January stepped-up security to stop departures of small boats.

Ports have taken measures to lock down vessels after a fishing boat that was stolen in November from Boulogne-Sur-Mer reached Britain, and boats were tampered with in the small pleasure port of Gravelines, between Calais and Dunkirk.

Reinforced security also means foot patrols on beaches, sometimes with helicopter support, and patrols on the Channel itself by France's Maritime Prefecture which coordinates rescues of the often off-course travelers.

Still to come are drones, part of a French-British action plan still being developed.

Planned long before the spike in small boat crossings, a new Joint Information and Coordination Center, opened in November and staffed by French and British Border Force police, provides real-time information with images of the ports of Calais and Dunkirk, the Eurotunnel and Eurostar information.

The high-tech detection is likely to only make Ahmed's life worse in his small camp, shot through with ethnic and religious divisions.

His wife and children are currently housed in a small apartment, on doctor's orders, but that is temporary.

He said he was beaten in the head by Muslims during a Bible-reading session, showing a photo of his bandaged head.

Calais - 15 January 2019

1. Ahmed (last name not given),37, Iranian refugee walking to the camp with food

2. SOUNDBITE (English) Ahmed, Iranian refugee:

"All try in the boat. And going to UK. Little people in here in Iranian (Everyone have tried to take the boat to the UK. Few Iranian people left)."

3. Ahmed walking to the camp with food

4. Various of migrants setting up tent

5. SOUNDBITE (English) Dariush (last name not given), Afghan refugee:

"We sleep in the street, or we sleep here in Calais. Because of that, we want to go to UK. It's not important, we die in here in the tent or we die in a river and sea."

6. Tents in the field

7. SOUNDBITE (English) Dariush, Afghan refugee:

"It was difficult, and now it's maybe very difficult after this (Brexit). But we will try because you can see it as well, we can't live in here (for) about one year and six months or even more than that. But we will try. Maybe we can go to UK and make our life (there)."

8. Kettle being heated on fire

9. Ahmed and refugees seated by fire

10. Various of the camp

11. SOUNDBITE (English): Ahmed, Iranian refugee:

"Two children go down in the water. After two friends, after eight friend helped me (to) for move my children up (on the) boat. After one hour, we come back on the beach."

12. Various of Ahmed visiting his wife and children in hospital dormitory, where they recovered after incident with the boat

13. Ahmed covers his face with hands, UPSOUND (English): "Very dangerous the boat."

14. View of Calais from dormitory

Calais - 16 January 2019

15. Exterior of the Joint Information and Coordination Centre (JICC)

16. Policeman looking at screens

17. SOUNDBITE (French) Franck Toulliou, deputy chief of the local Air and Frontier police department:

"In terms of the level of controls (after Brexit), there won't be more or less. We'll check (all vehicles), 100 percent: all the heavy vehicles, all tourism vehicles will be checked at the same level."

18. Various of people working inside coordination centre

19. SOUNDBITE (French) Franck Toulliou, deputy chief of the local Air and Frontier police department:

"The first reason is the proximity of Brexit. The fear of migrants has reinforced the border controls. Although it has already proven itself effective."

20. Various of migrants take away their belongings as police arrive to dismantle the campsite, some burning their belongings in small fires

21. Police pulling journalist away, who was working covering story at campsite

22. Police pulling away Associated Press cameraman

23. Various of workers cleaning the rubbish remaining at camp, police monitoring

24. Police leading away a migrant

25. Train coming out of the Eurotunnel

26. Barbed wire

Boulogne-sur-Mer - 16 January 2019

27. Various of the Port in Boulogne-sur-Mer

28. Empty seashore