​French ​coastguards ​have rescued ⁠157 people from ⁠a boat ​carrying migrants that ⁠caught fire in the English Channel.Three coastguard ships carried out the rescue and will ​take ‌them back ⁠to ​the port of Boulogne, said local administration. Five other ⁠migrants had been ⁠rescued from the same boat a few hours earlier by ​coastguards.According to refugee charity Utopia 56 eight English and French rescue boats were dispatched to French waters off Boulogne.They included Royal National Lifeboat Institution vessel was deployed from Eastbourne on the south coast of England at around 6am.A fuel leak from the outboard motor is believed to have caused the blaze, causing mass panic on board.A spokesman for France Maritime Prefecture said: “A small boat caught fire at the border between French and British waters, leading its occupants to jump into the water.”The spokesman said that after the five people were rescued "the remaining people on board refused the assistance offered by the French patrol boats".At that stage it was decided not to intervene further due to the "structural fragility" of boats used to cross the Channel.Prime Minister Andy Burnham standing by a migrant boat. Getty ImagesShow caption: Prime Minister Andy Burnham standing by a migrant boat. Gett…But after the engine caught fire this morning the "vessel's integrity deteriorated very rapidly".The rescue comes day after Prime Minister Andy Burnham said his Labour government will be "relentless" tackling the number of migrants arriving in the UK on small boats.Migrants have been seen cramming on to small boats off the coast of northern France to take advantage of good weather in the English Channel.The rescue comes after four asylum seekers have died trying to cross the English Channel in small boats on July 30.In one incident, they said, three women suffered heart attacks after their boat launched off the coast of Dunkirk, northern France.A boat also sank late on Wednesday off the coast of the French seaside town of Neufchatel-Hardelot, leading to the death of one man.The women, reportedly aged about 20, 30 and 50, were brought ashore by the French emergency services, but attempts to resuscitate them failed, and all three were declared dead.They were on one of the so-called taxi boats operated by human-trafficking gangs that were sailed along the coast to pick up people at designated spots before attempting the crossing.The total number of migrants who have crossed the Channel so far this year has reached 13,748, which is around 45 per cent lower than this time last year.But while the number of migrants has been falling and represents a victory for the UK government, the average number per boat has been rising.This has been attributed to the French authorities intercepting boats and disrupting the supply chain for the vessels' components. That has forced smugglers to cram more migrants on to “mega dinghies” to maintain their profits.The larger volumes have been blamed for deaths, as more people cram on to the boats, increasing the risk of suffocation or drowning.