A series of sexual assaults that terrorized the Seventh Police District community in late 1997 and into 1998 have been linked, through DNA testing, to a man who was shot and killed in Jacksonville, Fla., earlier this year. The resolution of these cases represents the first "cold" hit through the National DNA Index System (NDIS), according to the DNA Analysis Unit of the FBI Laboratory . A "cold" hit occurs when an association between either an offender or a crime scene is made through the matching of DNA evidence, without any other investigative lead.

Six previously unsolved cases that occurred in Southeast Washington, D.C., have been confirmed as linked to three sexual assault cases under investigation by the Jacksonville Sheriff's Office . Five of the sexual assaults, known as the "7D rape" cases, occurred in late 1997 or early 1998. The sixth case occurred in July 1998. Two of the Florida sexual assaults, referred to as the "Jamaican rapist" cases, occurred in the spring of 1998; the third took place in September 1998.

In early June 1999, the Florida Department of Law Enforcement (FDLE) Laboratory compared DNA profiles in NDIS to a DNA profile from one of the Jacksonville cases. The FDLE notified the FBI Laboratory of the possible association between the three Florida cases and a sexual assault in the District of Columbia. At that time, the FBI Laboratory, which analyzes and uploads DNA profiles to NDIS from D.C. sexual assault cases, entered additional profiles from District cases and informed the FDLE that five other assaults from Southeast D.C. had been linked through DNA profiling. Subsequently, in early July, Leon Dundas, 38, was identified as the assailant in all of these cases following analysis of a blood sample by the FDLE Laboratory. The blood sample was taken from Dundas after he was shot in the back and killed on March 8 in Jacksonville.

Following is a list of the Seventh District sexual assaults confirmed as linked to Leon Dundas:

• November 5, 1997: 100 block of Elmira St., SE; victim 18 years old
  
• November 9, 1997: 638 Condon Terrace, SE, inside abandoned building; victim 18 years old
  
• December 1, 1997: 4300 block of First St., SE; victim 14 years old
  
• December 18, 1997: 4600 block of Livingston Rd., SE; victim 14 years old
  
• January 6, 1998: 1800 block of Stanton Rd., SE; victim 21 years old
  
• July 23, 1998: 2500 block of Elvans Rd., SE; victim 20 years old

In addition, two other D.C. sexual assault cases may also be connected to Dundas, pending the outcome of DNA analysis on those samples:

• October 14, 1997: 4200 block of South Capitol St., SE; victim age unknown
  
• November 21, 1997: 3400 block of 19th St., SE; victim 17 years old

The FBI announced the creation of NDIS in October 1998. NDIS enables public forensic laboratories throughout the United States to exchange and compare DNA profiles electronically, thereby linking unsolved serial violent crimes to each other and to known sex offenders. Currently, 14 states and the District of Columbia participate in NDIS, which contains approximately 180,000 DNA profiles. All 50 states have been invited to participate in NDIS, and it is the FBI's goal to ultimately have all 50 join.

Metropolitan Police Chief Charles H. Ramsey praised the use of DNA technology as a critical crime-fighting tool for the 21st Century. "This case demonstrates both the power of this new technology and its usefulness in helping different agencies share crucial evidenciary information and solve crimes. This linking of the 7D rape cases to the now-deceased offender in Florida does not change the pain and suffering felt by the victims and their families, but it does offer them -- and the entire 7D community -- some peace of mind to know who committed these heinous crimes and that he will never strike again," the Chief said.

For additional information about this case and the NDIS system in general, contact: