HAYS COUNTY, Texas -- The death toll from the floods in Texas and Oklahoma now stands at 20. Fourteen people are still missing, and now drones are being used in the search for them.
A group of searchers from Texas A&M University -- Corpus Christi received permission from the FAA to experiment with drones in search operations such as this one.
The drones can fly low over the debris field and send back live video. If they spot something out of the ordinary, a team of searchers go in on foot or by boat. Some of the drones use thermal imagery to detect body heat - and even decaying biomass.
For Chip Urban, the search is personal. He knows many of the missing.
"When we heard about it, our heart sank and like so many in Corpus Christi, our first thought was how can we help?," Urban told CBS News.
Laura McComb, a 34-year-old mother of two who volunteers for the American Cancer Society, is still missing along with her six-year-old son Andrew, who enjoys kayaking and fishing; and her four-year-old daughter, Leighton, who likes to dress up in frilly dresses.
McComb's husband, who is also father to the children, is recovering from injuries sustained in the flood.
Also among the missing are Ralph and Sue Carey, and Randy and Will Charba. Michelle Charba, a wife and mother, was killed in the flood.
Family and friends of the missing have come together and have vowed to not stop looking.
"This effort is not over. We are 100% committed to finding Laura, Andrew, Leighton, Randy, Ralph and Sue," Kellye Burke tells CBS News.