BATON ROUGE, La. (AP) — St. John the Baptist is using chlorine to flush a water system on the east bank of the Mississippi River after tests showed the presence of a dangerous amoeba.

The state Department of Health and Hospitals said the Naegleria fowleri (nuh-GLEER'-ee-uh FOW'-lur-ee) amoeba was found in the water system serving more than 12,500 people in the Reserve, Garyville and Mount Airy communities.

No illnesses or deaths have been attributed to the amoeba.

The water system began a two-month chlorination purge on Thursday. State and parish officials say the water is safe to drink.

The water system was sampled as part of a state surveillance program launched earlier this month.

State officials say swimming or diving in freshwater lakes and rivers is the most common way to contract the amoeba.