(CNN) -- Texas police on Friday released a composite sketch of a man they believe broke into the homes of four former members of the same sorority, then sexually assaulted them.





No name has been given for the suspect in the alleged break-ins and attacks, which took place between November 2010 and October 2011, according to a timeline from the Plano police.





Detectives, however, do have "a definite DNA profile on the suspect" after a crime lab report, the police statement noted.





Plano police in October released a video -- dated in April -- showing a man with a distinctive swagger who they believe is responsible. Snapshots from that video were distributed Friday.





The alleged assaults occurred in the cities of Plano, Coppell and Corinth, all suburbs of Dallas.





The alleged victims -- all females in their mid-50s to mid-60s -- were alumnae of the same predominantly African-American sorority: Delta Sigma Theta, according to police.





They offered similar descriptions of their assailant as being a black male in his late 30s to mid-40s, weighing from 275 to 300 pounds and standing between 5 feet 7 inches and 5 feet 9 inches tall.





"He made it obvious to our victims that he knew information ... about them personally," Plano police spokesman Andre Smith said this fall, adding that none of the women believes they knew their attacker in advance.





According to Corinth Police Capt. Greg Wilkerson, all the assaults occurred in "residential settings" between 9:15 p.m. and 4 a.m. when the victims were alone. The alleged attack in his city, 35 miles northwest of Dallas, took place on October 14.





The late-night setting, the fact the victims were often asleep and the alleged assailant's "attempts to conceal his identity" make it challenging to definitively identify the attacker, said Wilkerson.





Wilkerson said that the nature of the assaults suggest the alleged assailant was "possibly suspecting surveillance, spending some time around the areas ... prior to the attacks."





The police captain said authorities do not know how the suspect learned details of the victims, speculating it may have been over the Internet, by accessing an old directory or noticing would-be victims with Delta Sigma Theta jewelry, placards or other paraphernalia out in public.





Delta Sigma Theta President Cynthia M.A. Butler-McIntyre this fall issued a statement urging members in the Dallas area to take precautions.





"To think that our members are being targeted is disturbing and extremely disheartening," she said.
What did police distribute? Where were the four women attacked? What age is the alleged attacker? What was the description of the attacker? Who were attacked in their homes? What have Plano police done? Which sorority were the women members of? How many women were attacked?
a video in "residential settings" late 30s to mid-40s, black male in his late 30s to mid-40s, weighing from 275 to 300 pounds and standing between 5 feet 7 inches and 5 feet 9 inches tall. four former members of the same sorority, released a video Delta Sigma Theta, four
question: What did police distribute?, answer: a video | question: Where were the four women attacked?, answer: in "residential settings" | question: What age is the alleged attacker?, answer: late 30s to mid-40s, | question: What was the description of the attacker?, answer: black male in his late 30s to mid-40s, weighing from 275 to 300 pounds and standing between 5 feet 7 inches and 5 feet 9 inches tall. | question: Who were attacked in their homes?, answer: four former members of the same sorority, | question: What have Plano police done?, answer: released a video | question: Which sorority were the women members of?, answer: Delta Sigma Theta, | question: How many women were attacked?, answer: four