TRIPOLI - The number of bodies of migrants recovered on a Libyan beach since the weekend has risen to 87, a media official from the coastal city of Sabratha has said.

The bodies began washing up on the city's beach west of Tripoli on Friday, the official said. On Saturday, 41 bodies were found by a group of volunteers trained by the city council and sent to a morgue for DNA testing before being buried. The rest were found over the weekend, the official added.

Illegal migration from Libya booms in the summer months when the Mediterranean is generally calm and traffickers pack unsafe boats with migrants desperate to start a new life in Europe.

People smugglers have taken advantage of the chaos gripping Libya since the 2011 uprising that toppled and killed dictator Moamer Kadhafi to boost their lucrative business.

They cram migrants into boats that are small and unsafe for the perilous journey to Italy just 300 kilometres (190 miles) from Libya's shores.

Thousands of migrants try each year to make the sea crossing but many drown. More than 10,000 migrants bound for Europe, mostly sub-Saharan Africans, have died or gone missing in the Mediterranean since 2014, according to the United Nations High Commissioner for Refugees.

Meanwhile, Slovenian police said Tuesday they found 12 illegal migrants on a cargo ship arriving from Turkey, in what is thought to be the EU country's first case of its kind.

The nine stowaways from Syria and three from Iraq embarked with the help of two Turkish crew members who have been detained, police said in a statement.

The illegal migrants, discovered on Monday in the Adriatic port of Koper, have applied for asylum and were taken to an asylum centre.

They are believed to be the first migrants discovered stowed away in a boat travelling from Turkey to Slovenia.

Almost half a million migrants crossed Slovenia heading for Austria and Germany before the so-called Balkan route was closed earlier this year.