Detective Scott Conley died on Friday after a long battle with an illness, the Chelsea police chief announced.

Conley was a member of the Chelsea police force for nearly three decades, from February 1996 until his death.

"It is with deep sadness that we announce the sudden and tragic passing of our Brother in Blue," Chelsea Police Chief Keith Houghton said in a statement.

"We deeply feel this tragic loss and our thoughts and prayers are with Detective Conley's family and loved ones at this difficult time," he added. "Detective Conley's presence will certainly be missed. As we mourn his loss, remember Scott's ardent commitment to our community and his service to our nation as a veteran of the United States Army."

During his tenure in Chelsea, Conley was assigned to the department's first critical response team and received specialized training in tactical and urban operations with a focus on gang operations.

He was assigned as a task force officer on the Violent Gang Task Force operating out of the FBI's Boston field office in Chelsea. Conley was investigating transnational gangs operating between the US and Central America.

"We are saddened by the loss of Detective Scott Conley, active duty with the Chelsea Police Department, End of Watch March 15, 2024," the Massachusetts State Police said in a statement.

"Detective Conley provided tremendous assistance to MSP on many cases, including the takedown of the violent MS-13 gang," MSP added. "He has made the streets of Chelsea safer for everyone who lives, works and raises families there. Our prayers are with her husband and children."

Conley had traveled to Central America, particularly El Salvador, several times as an advisor to the US State Department. Then in 2017, Conley was asked to testify before Congress as an expert on border security and the rise of transnational gangs in the country.

"We will honor Detective Conley's memory by continuing to serve with the professionalism, dedication and compassion he exemplified," Chelsea's police chief said.