A boat reportedly packed with people from Africa and South Asia bound for Italy has sunk off the Libyan coast, raising fears that dozens have died.
A security official in Zuwarah, a town in the North African nation's west from where the overcrowded boat had set off, said on Thursday there were about 400 people on board.
While an official death toll has not been announced, sources told Al Jazeera that dozens of people died in the incident, with many reported to have been trapped in the cargo hold when the boat capsized.
Blog: Why Al Jazeera will not say 'Mediterranean migrants'
By late in the evening, the Libyan coastguard had rescued about 201 people, of which 147 were brought to a detention facility for "illegal migrants" in Sabratha, west of the capital Tripoli, the security official was cited by Reuters news agency as saying.
Another local official and a journalist based in Zuwarah confirmed the sinking but also had no information on casualties.
The people on board had been from sub-Saharan Africa, Pakistan, Syria, Morocco, and Bangladesh, the Libyan security official said.
The Italian coastguard, which has been coordinating rescue operations with the European Union off the Libyan coast, could not confirm a sinking.
Libya's coastguard has very limited capabilities, relying on small inflatables, tug boats and fishing vessels.
Al Jazeera's Claudio Lavanga, reporting from Rome, said according to accounts by survivors, most of the people who had died were locked inside the hold of the boat.
"We've seen this many times before, only a few days before 50 refugees died because they were held in the hold," Lavanga said.
"Sometimes they die of suffocation and sometimes they drown because they can't escape after the boat capsizes...these are people who don't have the money to pay for a 'deck' position."
Zuwarah, Libya's most western town located near the Tunisian border, is a major launchpad for smugglers shipping refugees and migrants to Italy.
Libya has turned into a transit route for people fleeing conflict and poverty to make it to Europe.
Cross-border smuggler networks exploit the country's lawlessness and chaos to bring Syrians into Libya via Egypt or nationals of sub-Saharan countries via Niger, Sudan, and Chad.
More than 2,300 people have died this year in attempts to reach Europe by boat, compared with 3,279 during the whole of last year, according to the International Organization for Migration.
Speaking to Al Jazeera, Anas El Gomati, who founded the Tripoli-based think-tank The Sadeq Institute, said Libya's government does not feel it should be helping pay the bill to deal with refugees making their way to Europe as it is facing continued violence across the country.
"Libya's security approach - and security apparatus - is now completely disorganised and in chaos," he said.
"You have hundreds of different groups that are operating on the ground now, some of them taking advantage of a very, very chaotic situation - one of civil war."
On Thursday, 71 refugees were found dead in a parked lorry in Austria near the Hungarian border on Thursday.
German Chancellor Angela Merkel said the discovery had shaken European leaders discussing the refugee crisis at a Balkans summit.
Libya has been struggling to cope with an influx of foreigners, putting them in overcrowded makeshift detention facilities such as schools or military barracks where they live in poor conditions lacking medical care.
Libya used to deport people it caught but with fighting between armed groups having cut off land border crossings to Niger, Algeria, and Chad many stay months or years in detention facilities.
Source: Al Jazeera and agencies