KORONADAL CITY, Philippines – (UPDATE) At least 18 persons, including children, have died after cholera struck a village populated mostly by "lumad" (indigenous people) in Palimbang, Sultan Kudarat, the town's mayor said Wednesday.

Mayor Samrod Mamansual said at least 50 others have fallen ill to the water-borne disease, which hit sitio (sub-village) Bian in Barangay (village) Milbuk starting Monday.

"This is alarming," he said.

Mamansual told the Philippine Daily Inquirer (parent company of INQUIRER.net) that health workers have been sent to the affected area and residents needing intensive medication have been sent to the town center.

"Additional medicines will be transported to the area to prevent the spread of the disease," he said.

Mamansual said while health workers tend to the afflicted, other local agencies will try to trace where the residents contracted the disease.

Members of the Philippine National Red Cross have been dispatched to the affected villages, a local television station reported Wednesday.

Cholera, which is characterized by acute diarrhea, can cause severe dehydration and kidney failure, resulting in death.

Three months ago, eight people caught sick and died Barangay Ligaw.

In Maragusan, Compostela Valley, officials said the number of residents affected by the diarrhea outbreak there has reached around 800.

Compostela Valley Governor Arturo Uy said he has ordered a more thorough investigation into the cause of the outbreak, which affected most of the town's 24 villages.

"As per data from our health officials the number of persons affected reached at least 800. This number included those who did not go to the local hospital and to the municipal gym, which was converted into a makeshift medical facility, but instead opted to [resort to] home cures," Uy told reporters.

Uy said many patients have been improving after being treated by health workers.

He said the situation in the affected areas was also improving.

"The number of victims seeking consultation is now dwindling," Dr. George Arvin Legaspi, acting provincial health officer, said.

Legaspi said health workers are working double-time to arrest the spread of the disease.