Trenton, NJ ( PBN) Mercer County– In a significant move to strengthen law enforcement leadership, Mercer County Prosecutor Angelo J. Onofri and Chief of Detectives Jessica Plumeri have announced the promotions of several distinguished officers. Brian Kiely has been promoted to deputy chief, Nancy Diaz to captain, Richard Sheppard to lieutenant, and Ahmad Mansur to sergeant. Notably, Capt. Diaz’s promotion marks her as the highest-ranking Latina in Mercer County law enforcement history.

Deputy Chief Brian Kiely

Deputy Chief Brian Kiely commenced his law enforcement career in 1999 as a civil investigator at the Division of Criminal Justice after graduating from John Jay College of Criminal Justice. His extensive background includes investigating organized crime, money laundering, and narcotics, with a year spent at Newark Liberty International Airport as part of a U.S. Customs Narcotics Interdiction Task Force.

Since joining the Mercer County Prosecutor’s Office in 2006, Kiely has become a key figure in narcotics investigation and an expert witness in narcotics trafficking, contributing to numerous convictions in homicide, racketeering, and drug-related cases. He is also the chief humane law enforcement officer, overseeing the update of written policies, procurement of equipment, and managing law enforcement technology projects.

Deputy Chief Kiely actively participates in community outreach and restorative justice, volunteering at community events, including the Special Olympics, and serving as an Eagle Scout advisor and scoutmaster for Boy Scout Troop 180A.

Captain Nancy Diaz

Capt. Nancy Diaz, a graduate of the InterAmerican University of Puerto Rico, began her law enforcement career in 1998 with the Trenton Police Department. She joined the New Jersey Division of Criminal Justice Office of the Insurance Fraud Prosecutor in 2001 and graduated from the New Jersey Division of Criminal Justice Police Academy in 2003.

Capt. Diaz joined the Mercer County Prosecutor’s Office in 2005 and has served in every unit throughout her career. She gained recognition for her role as lead detective in the Art All Night shooting investigation in 2018, which led to her promotion to sergeant, making her the first Latina sergeant in the office’s history. Capt. Diaz has supervised multiple units, including the Homicide Task Force, Serious Collision Response Team, and the Shooting Response Team.

Celebrating her 25th year in law enforcement, Capt. Diaz is supported by her husband, Jesse, and their daughter, Arianny.

Lieutenant Richard Sheppard

Lt. Richard Sheppard joined the Mercer County Prosecutor’s Office in 2010 after graduating from the New Jersey Division of Criminal Justice Academy. With experience in the Trial Unit, Special Investigations Unit/Mercer County Narcotics Task Force, and Homicide Task Force, Lt. Sheppard has led numerous high-profile investigations, including those involving the “H-Block” gang.

As a certified instructor with the New Jersey Police Training Commission, Lt. Sheppard teaches at various narcotics schools and is a certified firearms instructor. He has served as vice president of PBA Local #339 and is currently president of the Superior Officers Association.

Sergeant Ahmad Mansur

Sgt. Ahmad Mansur began his law enforcement career with the Trenton Police Department in 2006. He joined the Mercer County Prosecutor’s Office in 2012, working in various units including Grand Jury, Trial, Special Victim, Insurance Fraud, and Domestic Violence. In 2022, Sgt. Mansur was promoted to officer in charge of the Special Victims and Internet Crimes Against Children (ICAC) units.

An advocate for the City of Trenton, Sgt. Mansur engages actively with the community, particularly with city youth in the Trenton Public School System.

These promotions follow the retirement of Deputy Chief Bryan Cottrell on June 1 and signify a continued commitment to excellence and diversity within the Mercer County Prosecutor’s Office.

Thomas Peterson is the Editor in Chief and founder of Peterson’s Breaking News of Trenton. Thomas founded PBT in 2012.