Updated

The death toll from Harvey has risen to at least 18 as three more fatalities have been confirmed in the Houston area.

The Harris County Institute of Forensic Sciences updated its storm-related deaths Tuesday night to include an 89-year-old woman, Agnes Stanley, who was found floating in 4 feet of floodwater in a home.

A 76-year-old woman was found floating in floodwater near a vehicle. Her name was not released. A 45-year-old man, Travis Lynn Callihan, left his vehicle and fell into floodwaters. He was taken to a hospital, where he died Monday.

Family members and authorities have reported at least 18 deaths although the bodies of some victims apparently swept away in the floodwaters have not been found.