Investigators in several states are still trying to track down the killer of 13 women, several of whom were Indian.

All of the women were prostitutes or suspected prostitutes who frequented truck stops in Oklahoma, Texas and nearby states. All of the women were Indian or White.

One of the most recent victims was Casey Jo Pipestem, 19, a member of the Seminole Nation of Oklahoma. She had been badly beaten and raped before her body was dumped off an overpass in Texas in January 2004.

So far, police have identified three persons "of interest" -- all of whom are truck drivers or former truck drivers.

Get the Story:
No suspects in slayings, only 'persons of interest' (AP 12/8)

Related Stories:
Slain Seminole woman promised to return home (04/06)
Investigators in six states probe murders of women (02/27)
Authorities looking into murders of Indian women (2/17)
19-year-old Seminole woman beaten to death (02/05)