Local and federal agents investigating whether Scott Kimball killed as many as 21 people in Colorado and across the West strongly suspect the serial killer fatally strangled and dismembered a woman in Westminster in 2004, said Dateline NBC correspondent Keith Morrison.

Federal and local agents have gathered circumstantial evidence linking Kimball to the killing of 26-year-old Catrina Powell, said Morrison, host of a Dateline NBC program on Kimball set to air Friday.

Morrison said he believes investigators are just “making sure everything is ready before charges are filed.”

Dateline’s Friday night broadcast will include profiles of Kimball’s Colorado victims and interviews with FBI agent Jonathan Grusing and others who have worked more than 12 years to hold Kimball accountable for all of his crimes.

The storyline includes the FBI’s role in getting Kimball released from prison in order to be their confidential informant. Kimball’s link to the FBI was a huge embarrassment to the federal agency because some of the killings happened within months after his prison release.

“Grusing has pretty much devoted the rest of his career to making it right,” Morrison said.

Dateline explores Kimball’s possible ties to many more killings than previously reported, including the death of an unidentified woman known as the “maiden water victim,” whose body was discovered in Utah in 1998, said Dateline producer Robert Dean.

Early in the morning of Oct. 25, 2004, Powell’s nude body was discovered in an alley next to a dumpster behind the Country Meadows strip mall at 7530 Sheridan Blvd., in Westminster. Her hands had been chopped off.

“The theory was that she was taken off Colfax Avenue and brought to Westminster by her killer,” Dean said.

Kimball is serving a 70-year sentence for four murders committed between 2003 and 2004. He’s also serving 48 years for fraud and 70 months on a federal gun charge.

Grusing has spoken to Kimball off and on for years in an attempt to learn about other homicides the serial killer has never been charged with committing and to learn the location of the remains of 25-year-old Jennifer Marcum, one of the Colorado victims he was convicted of killing, Morrison said.

Kimball was released from prison on Dec. 18, 2002, to act as an FBI informant after convincing federal agents that his cellmate, Steve Ennis, had asked him to kill a witness in a drug case.

Less than a month after Kimball’s release, LeAnn Emry, 24, of Centennial, vanished. Ennis’ girlfriend, Marcum, a Glendale stripper, disappeared a month later. Then Kaysi McLeod, 19, of Thornton, went missing in August 2003. Kimball’s uncle, Terry Kimball, 60, of Lafayette, vanished in mid-2004. Scott Kimball was the last to see each of them alive. In early 2006, after Kimball was named a suspect in yet another check-fraud case, he fled to California, where he was arrested after a televised car chase and standoff.

In 2006, the fathers of McLeod and Marcum pressed the FBI for a new investigation and Kimball’s elaborate web began to unravel. He ultimately agreed to plead guilty to second-degree murder in the four killings. A hunter found McLeod’s remains in a forest in Jackson County in north-central Colorado in 2007. Kimball eventually led authorities to Emry’s body in a Utah canyon and to his uncle’s remains in a forest near Vail Pass.

Last October, Kimball was charged on suspicion of attempted murder and escape while at Sterling Correctional Facility. The case is pending.

Dateline reached out to Kimball, who was willing to speak on his terms, but Morrison said the serial killer seemed to enjoy playing games and declined an interview before the show’s airing.

“We are not going to play a game,” Morrison said.