Laboratory tests showed signs of microbial contamination in all groundwater sources in the flood-hit city of Derna, the sanitation department has confirmed.

The department -affiliated with the Ministry of Local Government- also indicated that the leakage of sewage into the sea and the decomposition of bodies have led to chemical and bacterial pollution in the seawater.

Teams on the ground are distributing chlorine and educating residents on how to prevent water poisoning and stay safe, the department added.

"Water samples are collected from various water sources and analyzed in specialized laboratories, and appropriate measures are taken based on the results of the analyses and the experts' recommendations," the sanitation team explained.

The teams have collected water samples from the shores and the seaport basin of Derna, besides the seawater desalination plant, a crucial source of fresh water to the city and its surrounding areas.

Earlier, the National Center for Disease Control (NCDC) urged residents not to use the groundwater network after it was mixed with sewage sources during the recent deadly floods. 

 In the meantime, the NCDC Head, Haider Al-Sayeh, said the situation was stable but called on citizens to drink sterile water.