Sky News cameras have filmed a dinghy carrying a dozen suspected migrants arriving on a beach in Kent.
Helicopter footage shows the group coming ashore in Dungeness, with several men sitting on the sand after disembarking.
It appears that several other groups have also managed to come ashore after making the dangerous journey across the English Channel.
High numbers of crossings are being attempted due to the warm weather.
According to the PA news agency, at least 430 migrants sailed across the Channel on Monday, surpassing the previous record of 416 that was set in September 2020.
Sky’s correspondent Ashna Hurynag, who is in Dover, said: “We have seen the UK paying France a lot of money to up surveillance – but we are talking about miles and miles of coastline that need patrolling.
“Once the police crack down on one of the beaches, you find that suspected migrants pop up elsewhere and again, the routine starts once more.
“It’s a bit of a cat-and-mouse situation for authorities in France, but also for the authorities here too.”
Women and children – some of whom were too young to walk – were among those who arrived yesterday. Some needed to be supported as they set foot on the beach.
Also on Monday, parliament debated plans to introduce sweeping reforms of the asylum system, with former prime minister Theresa May sounding warnings over the prospect of the UK sending asylum seekers to offshore processing centres – not dissimilar from the ones used by Australia.
Bella Sankey, director of charity Detention Action, said: “The Home Office’s anti-refugee Bill is political theatre that doesn’t even pretend to deal with the issue or make our system, safe, fair or efficient.
“We need a mechanism allowing refugees arriving at the UK border in France to be given safe passage, and until we have it, all else is noise and distraction.”
More than 1,850 people have reached Britain on small boats in July so far, according to PA analysis.
That is more than the 2019 total.