A boat carrying migrants capsized Wednesday off the coast of Egypt, killing at least 29 people and sparking an operation in which another 150 were rescued, officials said.

Search and rescue teams were looking for more survivors following the tragedy which took place off the Mediterranean port city of Rosetta, two police officials said.

It comes months after the EU's border agency Frontex warned growing numbers of migrants bound for Europe were turning to Egypt as a departure point for the perilous sea journey.

Smugglers often overload the boats, some of them scarcely seaworthy, with passengers who have paid for the journey.

"Twenty-nine people have died and five were injured when a boat carrying illegal migrants capsized off the coast of Rosetta," the health ministry said in a statement.

The total number of people who were on board the boat was not immediately clear.

The health ministry said hospitals were being prepared to receive more casualties.

More than 10,000 people have died crossing the Mediterranean to Europe since 2014, according to the United Nations.

With the closure of the Balkans route popular with migrants seeking to reach northern European countries, as well as an EU deal with Turkey to halt departures, asylum seekers have been turning to other options.

"Egypt is starting to become a departure country," Frontex chief Fabrice Leggeri said in an interview with the Funke group of German regional newspapers in June.

- 'Deadliest year' -

"The number of boat crossings from Egypt to Italy has reached 1,000 (so far) this year," he said.

More than 300,000 migrants who have crossed the Mediterranean so far this year from various points of departure, the UN said this week.

The number is down from 520,000 in the first nine months of 2015.

Despite the lower numbers attempting the dangerous sea crossing, fatality rates had risen, with 2016 on track to be "the deadliest year on record in the Mediterranean Sea," said the UN refugee agency (UNHCR).

In June, a boat capsized near Sicily, drowning at least 169 migrants.

Earlier that month, a boat carrying hundreds of migrants sank off the Greek island of Crete and the bodies 104 migrants washed up on a beach in Libya.

Different patterns have emerged in the two European countries, Greece and Italy, which receive the vast majority of migrants.

Arrivals in Italy this year stood at 130,411, on a par with the 132,000 people who landed over the same period in 2015, said the UNHCR.

But Greece has seen 165,750 migrants and refugees land on its shores this year, a 57 percent drop against 2015 figures.

Arrivals began falling after a March deal between the European Union and Turkey on curbing migrant flows across the Mediterranean.