CAIRO (AP) — A boat carrying migrants bound for Europe capsized in the Mediterranean Sea off the coast of Libya, drowning at least 43 people, the U.N. migration agency said Wednesday.

The International Organization for Migration (IOM) said the “tragic” shipwreck that took place a day earlier was the first maritime disaster in 2021 involving migrants seeking better lives in Europe.

In recent years, the EU has partnered with Libya’s coast guard and other local groups to stem such dangerous sea crossings. Rights groups, however, say those policies leave migrants at the mercy of armed groups or confined in squalid detention centers rife with abuses.

The IOM said coastal security forces in Libya’s western town of Zuwara rescued 10 migrants from the shipwreck Tuesday and brought them to shore. It said the dead were all men from West African nations, according to survivors.

The migration agency said the boat left the town of Zawiya early Tuesday and capsized a few hours later after its engine stopped working amid rough seas.

In the years since the 2011 uprising that ousted and killed longtime dictator Moammar Gadhafi, war-torn Libya has emerged as the dominant transit point for migrants fleeing war and poverty in Africa and the Middle East.

Smugglers often pack desperate families into ill-equipped rubber boats that stall and founder along the perilous Central Mediterranean route.

The Libyan coast guard Wednesday intercepted at least 48 migrants, including 11 children, and returned them to shore, the IOM said.

The U.N. migration and refugee agencies called for an “urgent and measurable shift in the approach” to the situation in the Mediterranean, including an end to migrant returns to “unsafe ports.”

“Arbitrary arrests and arbitrary detention in the direst of conditions continue (in Libya). Many are victimized and exploited by traffickers and smugglers, held for ransom, tortured, and abused,” they said in a statement Wednesday.

An Associated Press investigation in 2019 found that militias in Libya tortured, extorted and otherwise abused migrants for ransoms in detention centers under the nose of the U.N., often in compounds that receive millions in European money, paid to Libya’s government to slow the tide of migrants crossing the Mediterranean.

The IOM said in November that some 500 migrants have died trying to cross the central Mediterranean, but the actual number of people who lost their lives could be much higher, due to “the limited ability to monitor routes.”