Eurokinissi/Reuters
Migrants arrive at the port of Kalamata in Greece on June 14, 2023.
CNN  — 

At least 78 people died after a migrant boat carrying hundreds of people sank off the Greek coast in the early hours of Wednesday, that country’s Coast Guard said, as fears mount that there could be more fatalities.

A total of 104 migrants who were traveling on the boat have since been rescued from the water and transferred to the city of Kalamata.

“All the men who have been rescued are between 16 and 41 years old according to what they said,” Kalamata Mayor Thanasis Vasilopoulos said Wednesday. “They also said there were women and children on board,” he added.

The coast guard, which revised down a previous death toll of 79, said the search and rescue operation will stop once it’s dark in the area and will continue with the first light of day tomorrow.

It is unclear how many people were on board the ship when it went under. Survivors say there could have been as many as 750 passengers.

Hellenic Coast Guard
The Greek coast guard released photos of the boat taken on Tuesday before it sank on Wednesday.

“We fear that the number of dead will rise significantly,” a spokesperson for Peloponnese prefect Panagiotis Nikas said.

The International Organization for Migration (IOM) earlier tweeted that it believed that there were “up to 400 people” onboard.

UN chief Antonio Guterres referred to the shipwreck as “horrific” in a post on Twitter, adding: “As I’ve said before – every person searching for a better life deserves safety and dignity.”

State broadcaster ERT, citing initial information from authorities, said the boat had sailed from Tobruk, in Libya.

The NGO Alarm Phone said it first received a call from the boat Tuesday afternoon and that it was “difficult to communicate with the distressed,” who said that they could not survive the night.

www.argolikeseidhseis.gr/AP
Survivors arrive by yacht after a rescue operation at the port in Kalamata town.
Stelios Misinas/Reuters
People rest in a shelter, following a rescue operation, after their boat capsized at open sea.

Those on board said the captain left the vessel three hours after the first distress call was made and passengers were in need of food and water, accoring to Alarm Phone.

A merchant vessel is said to have provided the boat with water at around 8 p.m. local time on Tuesday evening.

The last time Alarm Phone was able to contact the boat was just before 1 a.m. local time on Wednesday morning. According to Alarm Phone, all that could be heard was “Hello my friend… The ship you send is…” before the call cut off.

Search and rescue operations are being carried out by the Coast Guard in international waters, 47 nautical miles off the coast of Pylos in the southwestern Peloponnese.

The boat’s destination was Italy, according to Greek officials.

www.argolikeseidhseis.gr/AP
Survivors receive first aid.

Greek President Katernina Sakellaropoulou visited some of the survivors on Wednesday. “We are shocked, we are shocked like everyone in Greece,” Vasilopoulus said.

Greece has been at the heart of the European migrant crisis, offering a way into the European Union for migrants and refugees coming from the Middle East, Asia and Africa.

The number of undocumented people arriving on European shores by sea has skyrocketed this year due to conflict, global inequality and the climate crisis.

View this interactive content on CNN.com

More than 36,000 people arrived in the Mediterranean region of Europe from January to March this year, nearly twice the number compared with the same period in 2022, according to figures from the UN’s refugee agency (UNHCR).

It is the highest number since the refugee crisis that peaked in 2015 and early 2016 – during some of the fiercest fighting in Syria’s civil war – when the arrival of more than 1 million people on Europe’s shores led EU solidarity to collapse into bickering and border chaos.