A small boat carrying migrants trying to cross the English Channel ran aground on a beach in northern France early Sunday, leaving two people dead and 16 others injured, authorities said.

The incident involved a vessel with 82 people that set out overnight from Hardelot, a few kilometers south of the port of Boulogne-sur-Mer. Christophe Marx, secretary-general of the Pas-de-Calais prefecture, said the boat’s engine failed and it began to drift before the vessel ran aground on the shore.

French maritime gendarmerie personnel rescued 17 people and took them to Boulogne-sur-Mer. Marx said the makeshift boat ran aground with 65 others still on board.

Marx said two women were found dead, most likely from suffocation. He said they were believed to be in their 20s and to have come from Sudan, and he said an investigation was underway.

Marx said some of the deadliest risk on such boats comes from overcrowding and restricted breathing. He said the women were believed to have been “crushed or asphyxiated, as unfortunately often happens on boats … where too many people are packed in,” according to his remarks to reporters.

Authorities also said three of the injured were in very serious condition after burns caused by fuel at the bottom of the boat. Others were hurt in the incident, which French officials treated as part of an ongoing pattern of dangerous attempts to reach the United Kingdom by sea.

The deaths came as officials and aid groups continue to document fatalities linked to the channel crossing. The crash was the third deadly incident involving migrants attempting the trip in just over a month.

In April, two men and two women died while trying to board an inflatable boat off the coast of northern France, and British authorities arrested a man from Sudan on suspicion of endangering life in that case. A week earlier, two other people died in similar circumstances off the coast north of Calais.

The United Kingdom and France signed a new multimillion-euro deal last month that aims to reduce the number of crossings by increasing police patrols and enhancing surveillance in northern France. So far this year, more than 6,000 migrants have reached the United Kingdom after crossing the channel, down 36% from the same period last year, though authorities said the change may partly reflect more unsettled weather.

Before Sunday’s deaths, migrant aid group Utopia 56 said at least 172 people have died at the French-U.K. border over the past three years, including 123 at sea.