Derna, in eastern Libya, was wrecked when storm waters overwhelmed two dams sending a torrent through the city centre early on Monday and sweeping whole districts into the sea.
"If a huge flood happens the result will be catastrophic for the people of the wadi and the city," wrote hydrologist Abdelwanees A. R. Ashoor of Libya's Omar Al-Mukhtar University. Libya has had no government with a nationwide reach since a 2011 uprising that toppled longtime autocrat Muammar Gaddafi. Rival factions have splintered the country, cities were pitted against each other and state funds diverted by corruption.
Few places in Libya have emerged unscarred from conflict that has swept the whole nation, but Derna was particularly badly hit by fighting since 2014 and by its seizure by Islamic State militants, who were then ousted by rival jihadist groups. Although many governments have official contacts with Haftar and the eastern-based parliament, Libya's divisions mean there are rival layers of officialdom when dealing on a national level, including when sending aid.