The UK’s National Crime Agency (NCA) said it has made one more arrest in connection with the deaths of five people on a Channel small boat on Tuesday.
The NCA said it had arrested an 18-year-old Sudanese citizen on Wednesday.
One of the three people arrested on Tuesday had been released without charge, while the other two remain in custody, it added.
The boat was carrying 112 people when a deadly crush happened.
The NCA said the Sudanese citizen was currently being questioned.
A 19-year-old from Sudan who was initially detained on Tuesday evening was released without charge, the NCA said, adding that he would now be dealt with by immigration authorities.
Two other men – a 22-year-old Sudanese national and a 22-year-old from South Sudan – remain in custody.
The vessel initially ran into trouble early on Tuesday morning, with police witnessing people entering the water from the overcrowded vessel.
It was one of several small boats which left France at about 03:00 local time (02:00 GMT) during favourable weather conditions.
Upon seeing the boat in distress, French regional prefect Jacques Billant said the Abeille Normandie patrol boat was immediately deployed to rescue those who had set off on the boat. When they arrived, several people were “unconscious and in great difficulty”.
Six people were taken aboard the patrol boat, before being taken to the beach to be treated by emergency services.
Another 47 people were rescued from the boat by French authorities, according to Mr Billant, but a further 55 remained on board as they did not wish to be rescued. They were among a large group of migrants who arrived in Dover late on Tuesday.
 said it has made one more arrest in connection with the deaths of five people on a Channel small boat on Tuesday.){kind=link}