The search and rescue operation following the sinking of a fishing vessel carrying hundreds of migrants off the Greek coast was drawing to a close on Sunday.

The mission to find survivors was extended until the end of the weekend but has not produced any fresh news on the fate of the passengers or how many remain missing.

It has left relatives and friends distraught and desperate for information.

Between 400 to 750 people were believed to be aboard the boat, according to a joint statement from the International Organization for Migration and UN Refugee Agency.

‌Since the boat capsized on Wednesday, the number of missing, presumed dead, is still unknown. Greek authorities put the figure at 250, while eyewitnesses claim around 500 people remain unaccounted for.

With no new information coming from the coast guard or Kalamata city authorities, relatives of the missing have been rushing frantically to the asylum center in Malakasa (about 270km from Kalamata) where most of the rescued have been transferred.

Most who have arrived here have soon left empty-handed.

Kalamata, the second most populous city of the Peloponnese peninsula and in southern Greece, held a memorial service for the victims of the shipwreck, both known and unknown. 

The climate was tense and emotional as relatives of the dead and missing attended. 

On Sunday, Pakistan authorities arrested 10 alleged human traffickers. Every year, thousands of young Pakistanis embark on perilous journeys attempting to enter Europe illegally in search of a better life.

Local media said 300 Pakistanis may have died in Wednesday's tragic event. Officials said nine people had been detained in Pakistan-administered Kashmir - home to a majority of the victims - and one in Gujrat, a city that has long served as a springboard for migrants.

Relatives and activists told AFP that at least 141 Syrians were aboard.

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