Warning: This story contains details that some readers may find distressing

A masked doctor leans down into a black plastic body bag, and gently manipulates the legs of the man inside. “First we determine age, sex and length,” he explains.

“He’s in the putrefaction stage now, because of the water.”

In a hospital car park in the eastern Libyan city of Derna, the final details of one of its many victims are being carefully checked and logged.

This is now one of the most vital jobs here, and one of the most distressing. The man is unrecognisable after spending a week in the sea. His body washed ashore that morning.

Expert hands gently probe, looking for identifying marks and taking a DNA swab. That’s important, in case there’s a family still alive to claim him.

More than 10,000 people remain officially missing, according to figures from the UN’s Office for the Co-Ordination of Humanitarian Affairs.

The Red Crescent has been issuing its own numbers.

The UN says the death toll so far stands at some 11,300. The final total remains unclear – although the one thing that is certain is the sheer scale of this catastrophe.

Mohammed Miftah knows in his heart his family are among the victims.

When he went to find his sister and her husband at their home after the floods, it had been washed away.

He’s heard nothing from them since. He shows me a video he took as the torrent rose, brown water pouring in through his front door.

A car is carried on the current and wedges into the open space, blocking it completely.

“I saw cars coming down and I came out running,” he recalls.

“I thought that was it, that I was going to die. We could see our neighbours waving flashlights. In just a few moments, the lights went out, and they had disappeared.

“That was the hardest thing.”

As international aid begins to arrive in earnest, the Health Minister of Libya’s eastern government has announced that four Greek rescue workers were killed in an accident on the road to Derna.

Fifteen more were injured. They were on their way to join teams already on the ground from France and Italy.

Kuwait and Saudi Arabia have also flown in tons of extra supplies.

The next step is making sure they’re used properly and fairly.

Abdullah Bathily, the Head of the UN’s International Support Mission in Libya, told BBC Arabic the country now needs to create a transparent mechanism to manage all of its international donations.

It’s a concern borne from the well-known challenges of coordinating between the government in Tripoli which is internationally recognised, and the eastern Libyan government, which isn’t.

Back in the centre of Derna there are some points of light amid the mud and debris that has enveloped this city.

On one street corner, hundreds of colourful clothes lie scattered in piles.

Across the road a huge queue forms as fuel is handed out to survivors.

As the donations keep coming, one man arrives and places a box of warm scarves at the feet of an elderly woman.

He kisses her head tenderly, as she smiles and begins to choose one.

These are Libyans helping Libyans in one of their worst moments of crisis.