Up to 20,000 people feared dead after catastrophic floods in Libya

• Derna Mayor Abdulmenam al-Ghaithi told Saudi TV channel al-Arabiya that "based on the number of neighborhoods destroyed," he believes between 18,000 and 20,000 were killed in the storm.

International aid group Islamic Relief said on Thursday that the current death toll will likely double, and could quadruple in the coming days.

• "The floods are like a mini-tsunami destroying everything in its path," Salah Aboulgasem, deputy director of partner development at Islamic Relief, said in a statement. "Thousands of people have drowned and entire families have been wiped out."
• Officials have said that at least a quarter of Derna has been completely destroyed

What they're saying: "Cars and dead bodies barged into the house. We opened the doors and the water filled the floor, so we moved to the second floor," Abdel Gawi, a volunteer rescue worker, told the Washington Post.

• "The corpses [outside] were in the hundreds," Gawi added. "You open your door and see hundreds; they floated into the buildings from doors, from windows."

The big picture: Rescuers continue to search for survivors, but other efforts Wednesday and Thursday turned to finding bodies, including those washed to the sea, and burying them. Officials have expressed fears that decomposing bodies could lead to health and environmental problems.

• At least 3,000 bodies had been buried largely in mass graves outside of Derna as of Tuesday, the health minister for the east Libyan government said. Another 2,000 bodies were being processed for burial, according to AP.
• The UN and several international groups have sent teams to respond to the crisis, but destroyed or impassable roads and the lack of accurate and reliable data about the needs of those affected make providing aid especially challenging.
• At least 30,000 people have been displaced by the floods, according to the UN's International Organization for Migration. Nearly 900,000 people live in areas affected by the storm, according to the UN aid office.

The scale of the destruction underscores the vulnerability of a country that has been through years of chaos and fighting.

• Libya is currently ruled by two rival governments — one in the east and another in the west. Fighting, political instability and corruption have come at the expense of development and investment in infrastructure in many towns and villages.
• Some have pointed the finger at officials for not maintaining the dams, despite a budget being allocated to do so, per AP. Officials from both governments have called for an investigation.

World Meteorological Organization chief Petteri Taalas said on Thursday that the devastation also highlights the need for better "multi-hazard early warnings which embrace all levels of government and society."

• Libya's National Meteorological Center did issue early warnings ahead of the storm about the likelihood of heavy rainfall and flash flooding, but it did not stress the risk posed by aging and neglected dams.
• "The fragmentation of the country's disaster management and disaster response mechanisms, as well as deteriorating infrastructure, exacerbated the enormity of the challenges," Taalas said.

The UN has also pointed to the devastation as yet another "lethal reminder" of the effects of climate change.

• Feeding off the moisture and energy from the warm Mediterranean, Daniel developed into what is known as a "medicane," a Mediterranean tropical-like cyclone, Axios's Andrew Freedman reports.
• "Heavy rainfall events are occurring more frequently worldwide, and also are becoming more severe, which scientists have linked to the burning of fossil fuels," Freedman notes.

Go deeper: Record 110 million people forcibly displaced worldwide, UN says