The first sign that something was wrong was the dogs barking.
It was 2:30 in the morning and it was dark outside. When Husam Abdelgawi, a 31-year-old accountant from the eastern Libyan city of Derna, got up and drowsily walked down the stairs to check on them, he felt water under his feet.
Husam opened the front door of the house he shared with his younger brother, Ibrahim. He let in more water, ripping the door off its hinges.
The brothers ran to the back door, where they were greeted by a "horrific and unimaginable scene, worse than witnessing death itself," Husam said, in a telephone interview from the city of Al-Qubbah.
"The bodies of women and children were floating next to us. Cars and entire houses were trapped in the current. Some of the bodies were carried by the water to our house."
The water also swept Husam and Ibrahim away, taking them farther and faster than they imagined possible. In a matter of seconds, they were 150 meters away.
Ibrahim, 28, managed to grab hold of the floating power cables still attached to their poles and make his way back to where Husam was trapped. The brothers used the cables as ropes to crawl toward a nearby building and through a third-floor window, and from there they reached the fifth-floor rooftop, where they could wait out the flood.
"The area we were in was an uptown part of town," Husam said. "On the lower parts, I don't think anyone from the fifth or sixth floor has survived. I think they are all dead. May God have mercy on their souls."
Estimates of the death toll vary. Libya's ambassador to the UN says some 6,000 people have been confirmed dead and thousands more are missing. A Red Crescent official in Libya said about 10,000 people were believed to have died. The mayor of Derna has warned that 20,000 people could have lost their lives.
The flood was caused by the failure of two dams on the outskirts of Derna, unleashing a torrent of water through the center of the city.
"Derna was divided into two halves by the water and everything in between disappeared," said Rahma Ben Khayal, an 18-year-old student who managed to reach safety on a rooftop in the city. "All the people in the middle are dead," she said.
The torrent that swept away entire streets had begun a day before, in the form of light rain.
It wasn't scary at first, said Amna Al Ameen Absais, a 23-year-old medical student born and raised in Derna, who is guardian of her three younger siblings after the deaths of both parents from illness.
As raindrops drummed outside, the four brothers sat in their first-floor apartment in Beach Towers, a seven-story building along the boardwalk, playing games and browsing on their phones. They dressed their little brother in a life jacket and laughed.
But as Sunday night progressed, the rain became heavier. The sirens sounded. The brothers couldn't sleep.
"It really started around 2:30 in the morning," Amna said in a telephone interview from the nearby city of Tobruk. "The noise was getting louder. My brother said he could see water covering the street."
As the water rose, residents began to migrate upstairs. Amna grabbed the cat and four passports and went from her first-floor apartment to the third-floor apartment. "People were looking outside, in the dark, praying," she said. Then the water reached the third floor. "Everyone started screaming. We went up again, to the fifth floor and finally to the seventh floor."
Panic had taken over him. "I lost the cat," Amna said. "I lost my little brother for a minute but then I found him. I realized we couldn't even stay on the seventh floor, we had to go to the roof."
From there they could see the neighbors on the roof of a three-story building opposite, including a family they were friends with. The neighbors waved their telephone flashlights. Moments later, the entire building collapsed into the water in the darkness.
"It felt like an earthquake," Amna said. "That family hasn't been found yet. Their son is looking for them. We told him we saw their building collapse in front of our eyes."
Some members of Amna's own family are also missing. His uncle, his wife, and his three children lived in a nearby building that collapsed. "Our last call was around 9 p.m., he was calling to make sure we were okay," he said. "We haven't heard from him since."
Finally, Amna was able to escape from the building with her three brothers, after the waters subsided. Her street had completely disappeared. "It was like the earth had opened up," she said. "There's just a cavity left where the street used to be."
A neighbor she knew slipped and disappeared into the water in front of them, and her husband and son were unable to save her, Amna said. She learned that her best friend, Aisha, had not survived.
Amna and her brothers walked for hours to higher ground, passing dead bodies along the way. It seems that the death toll from the catastrophe will increase significantly. Husam Abdelgawi, the accountant, said he had already counted at least 30 friends among the dead and more than 200 acquaintances. "It's a miracle she survived," he said.
The damage suffered by Derna is catastrophic. Entire neighborhoods have been destroyed.
Mohamed al-Menfi, of Libya's internationally recognized government in the western city of Tripoli, said he had asked the country's attorney general to investigate; Anyone whose actions or inaction were responsible for the dams' collapse should be held accountable, he said.
The World Meteorological Organization said most of the loss of life could have been avoided if Libya had had a functioning meteorological agency: "They could have issued warnings. Emergency management authorities would have been able to carry out the evacuation of people. And we could have avoided most of the human casualties," said WMO chief Petteri Taalashe.
Many survivors are desperately waiting for news of their loved ones. Others are in mourning, for the dead and for Derna.
"I don't think I can ever go back," Amna said. "Those streets were my entire life. We knew every corner of the city. Now it's gone."
Riam Dalati contributed to this report.
