The Hellcats were an all-woman gang in Turkana City on planet Turkana IV in the 24th century.
They were a strong gang, controlling four blocks of the ruined city, with working electricity in one building that they lived in and defended like a fortress. Their chief enemies were the rape gangs that preyed on the women of Turkana.
In the year 2352, Tasha Yar decided to join the Hellcats for protection and better living conditions. She planned to offer her combat skills with a knife and her pet cat as a rat-hunter and mascot. However, she was captured by a rape gang, and rescued by Darryl Adin and an away team from the USS Cochrane, and taken off-world. (TNG novel: Survivors)