Agnieszka Agnes Ziemlewski, 26, was found shot to death on a Farmington walking trail on September 24, 1998. A Polish immigrant who came to the United States in the early 1980s, she was a University of Connecticut graduate working at United Health Care in Hartford. Her body was discovered near a gate on Old Mountain Road close to the West Hartford border; police say she was shot multiple times at close range and that her killing was not a random act.

The investigation generated hundreds of interviews and a standing $50,000 reward but produced no arrest for more than two decades. In 2018 Farmington detectives asked the FBI Behavioral Analysis Unit to review the case, prompting new interviews. In June 2020 Katherine Pires of East Hartford was arrested on allegations she provided a false alibi for a person of interest; she later pleaded guilty to a misdemeanor in December 2021 and received one year of probation, reportedly as part of a cooperation agreement. No one has been publicly charged with the murder itself and the case remains unsolved.