Reuters photographer Darrin Zammit Lupi has been on the Phoenix, a migrant rescue ship in the Mediterranean operated by Malta-based NGO MOAS since April 1. This past weekend, he witnessed some of the most dramatic scenes of his career. Below is the account of his experience.

They were three days of suffering, death and, most importantly, hope. From Good Friday to Easter Sunday, I experienced those raw emotions aboard a migrant rescue ship.

We saved thousands of migrants, counted the dead, and covered the shivering. All in a day's work for the crew of the Phoenix, one of the rescue ships plying the waters of the southern Mediterranean trying to make the sea less of a cemetery.

I started working on the migration story almost 19 years ago. In all this time, I've never experienced anything remotely close to what this Easter holiday weekend has been like.

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From the Phoenix, rescuers use Rigid Hull Inflatable Boats (RHIBs) to reach rubber dinghies or rickety wooden boats packed with migrants, usually from sub-Saharan Africa.

In one episode, on Good Friday, a group of migrants were issued with life jackets and lined up on the edge of their dinghy, ready to transfer to an RHIB. Suddenly one of them slipped and fell into the sea, taking 10 others with him.

A rescue worker lifts a man into a boat alongside the Dutch rescue ship Sea-Eye. At least seven people died while crossing the Mediterranean this weekend. Photo: Reuters/Darrin Zammit Lupi

Through my lens I saw two people going under. One stretched out a hand towards me from about 4 metres (yards) away. The rescuers jumped in and saved both. I put down my cameras and helped pull some on board.

The next day was intense in a different way.

Hundreds more people were taken on from rubber dinghies that surrounded the Phoenix, seeming at times like black beads of a large floating rosary.

By nightfall, Phoenix was already packed to capacity but we had to take another 70 people off one of the boats because it risked going under.

It was all hands on deck at this point. No time for photos. Cameras down, I was assigned to the rescue zone/embarkation doorway.

One crew member called it the "doorway to life". Archbishop Charles Scicluna of Malta called the "Door of Mercy", when he visited the ship before we set sail.

'Through my lens I saw two people going under. One stretched out a hand towards me from about 4 metres (yards) away.' Photo: Reuters/Darrin Zammit Lupi

My job was to clasp the hands of migrants who were on the rescue RHIBs and pull them up onto the Phoenix. I spent much of the rest of the night helping keep an eye on the new arrivals out on the bow, which is very rarely used for migrants as it's highly exposed to wind and water.

On Easter Sunday, although overloaded with 450 migrants, we headed to the scene of another rescue operation. We passed several empty life jackets and one dead migrant floating face down in the water. We would have to try and retrieve the body later. We needed to concentrate on the living.

At the scene, we helped the rescuers of another NGO ship, the Sea-Eye, take bodies off a flooded dinghy. Those migrants had died waiting to be rescued. I covered the face of a dead woman with a discarded shirt and said a silent prayer.

We took on seven bodies. Others may still be out there.

A child stands up on the MOAS ship Phoenix after being rescued in the central Mediterranean. Photo: Reuters/Darrin Zammit Lupi

As we sail towards Sicily to bring our human cargo to dry land, we are moving slowly. We are overloaded. The sea is not merciful today. If we move any faster, waves will break over the migrants, huddled and exhausted, on the bow.

For many, Easter Monday is a day of hope. For me, that hope was incarnated in the smile of a Somali mother when we rescued her and her 12-day-old baby.