(CBS/AP) DALLAS - Police racing to find a Dallas-area serial rapist who appears to be preying on members of a national black sorority have released a timeline of the attacks and additional details about a surveillance video.
Police say the video, which was recorded in April, is of a man who called one of the Plano victims from a convenience store payphone in Mesquite to inquire about her welfare after the April attack.
Plano police spokeswoman Heather Bowden says the victim doesn't know the man, adding, "we want to talk to this guy pretty bad."
Detectives have a definite DNA profile of the suspect, but haven't been able to match it to anyone so far, CBS Dallas reports.
Police in Plano, Coppell and Corinth are investigating at least four sexual assaults, all involving black womEn in their mid-50s to mid-60s who are Delta Sigma Theta members.
The North Texas Crime Stoppers program is offering a reward of up to $5,000 for information in the case, reports CBS Dallas.
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