Randy McIlwain, NBC 5
Three police departments lose hope of catching a serial rapist unless he commits another assault.
Police are appealing to the conscience of the man who has attacked at least four alumnae of a national black sorority.
The man has attacked at least four members of Delta Sigma Theta in home-invasion-style attacks since November 2010, sexually assaulting three of them. Women in Plano, Coppell and Shady Shores have been attacked.
"Read your conscience, follow your conscience, turn yourself in so you can put this behind you," said Andrae Smith, of Plano police.
A three-department task force of detectives from Coppell, Plano and Corinth have been working around the clock, following leads in hopes of making an arrest.
Investigators have video, photographs, DNA and an understanding of how the man has operated. Local and national news coverage has generated leads, but none that have led them to the attacker.
Police said they hope either someone will identify him or he will turn himself in as investigators keeping the video and photos of the man in the public consciousness.