Two more migrant boats have crossed the English Channel Wednesday morning, according to reports.
There were thought to be six people on one boat, and 13 on the other, the BBC reported.
The news comes a day after Border Force intercepted 86 men, women and children crossing from France - believed to be the highest number of migrants attempting to cross in a single day.
A Border Force patrol vessel was seen coming into Dover port on Wednesday morning, but no migrants were seen disembarking.
The news comes as a charity warned the imminent closure of a gym in Dunkirk where up to 1,000 migrants are living is likely to prompt a spike in crossing attempts.
Refugee charity Care4Calais expects French authorities to conduct forced evictions at Dunkirk and Calais this week, with hundreds of migrants displaced as a result.
Speaking to the PA news agency, charity founder Clare Moseley said the charity has been told the gym is to be closed following a failed court appeal.
Many of those living at the Espace Jeunes du Moulin gym are families with young children, some of whom have fled the Islamic State conflict in Iraq.
She said: “There has been a bit of uncertainty as to when it’s going ahead.
“The latest we have heard is it’s likely to be Thursday. We think the Calais one is probably going to be tomorrow.”
Moseley said the French government will offer evicted migrants alternative accommodations, but predicts a significant number will return to the coast, based on previous instances.
Asked if the closure of the gym will lead to an increase in attempted crossings, Moseley said: “Absolutely, yes. It’s not that they are not trying to cross now, because they are, but it can only make it worse.
“At the end of the day they are trying to get their families to safety.”
Last month, Home Secretary Priti Patel said urgent action was needed to put a stop to the wave of crossings, after she met French Interior Minister Christophe Castaner in Paris.
Early on Tuesday, two small vessels carrying a total of 23 people were intercepted by a Border Force cutter, which took the migrants to immigration officials for questioning.
They said they were Iranians, Afghans, Pakistanis and Filipinos, the Home Office said.
At about midday, a boat carrying 18 people near Dungeness, Kent, was taken to Dover by the Border Force, with 14 presenting themselves as Iranian, three as Iraqi and one as Vietnamese.
Around the same time, a boat carrying 23 people was also intercepted in the Channel, with those on board saying they were both Iranian and Ethiopian, the department added.
Two separate groups, who said they were from Iran, Iraq and Turkey, made it to beaches in East Sussex without being detected at sea, but were later detained and transferred to immigration officials.
The Home Office declared the matter a major incident under former Home Secretary Sajid Javid and pledged millions of pounds to tackle the crisis, dispatching the three Border Force cutters.
A plan drawn up in January included a £6 million investment in security equipment, CCTV coverage of beaches and ports and a commitment to return migrants under international and domestic laws, the department said.
A Home Office spokesman said: “We are working closely at all levels with the French authorities to tackle this dangerous and illegal activity.”
The number of migrants taken in by UK authorities so far this year is thought to have passed 1,000.