Protesters changing "Libya! Libya!" called on authorities to expedite their investigation into the disaster, for the UN to set up an office in Derna, for the urgent reconstruction of the city and for compensation for those affected by the flood.
Residents from the nearby cities of Benghazi and Tobruk have offered to put up the displaced, while volunteers search for survivors buried beneath the rubble.
Officials have warned that a disease outbreak in Libya's northeast, where floods have killed thousands, could create "a second devastating crisis" as diarrhea spread among those who drank contaminated water.
Protesters in Derna accuse Libyan authorities of inaction after deadly euronews.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from euronews.com Daily Mail and Mail on Sunday newspapers.
Residents from the nearby cities of Benghazi and Tobruk have offered to put up the displaced, while volunteers search for survivors buried beneath the rubble.