(credit: Plano Police Dept.)

PLANO (CBSDFW.COM) – As the investigation into a series of rapes in Plano continues, the police department believes they have a new tool in trying to solve the crime.

On Friday the department released a sketch of the suspect.  He’s accused of four attacks so far in the Collin County area.  All of the attacks have had one thing in common – the women in their 50′s & 60′s are all part of the same sorority, Delta Sigma Theta.

Because the suspect targeted a specific sorority, police held a safety class recently for women from the  sorority alumnae group.

Police also have a dna sample of the rapist but so far that has failed to produce an arrest.

The attacks have happened over a one-year period.  Plano police say their investigation is ongoing.

If you have any information on the case, they ask you call (972) 941-2148 or Crime Stoppers at (877) 373-8477.

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