H Block Gang Associate Sentenced to More Than Four Years in Prison for Drug Conspiracy

BOSTON - An associate of the violent Boston-based gang, H-Block, was sentenced today in federal court in Boston for drug conspiracy charges.

Mark Linnehan, 26, of West Roxbury, was sentenced by U.S. District Court Judge Leo T. Sorokin to 51 months in prison, to be followed by three years of supervised release. In January 2026, Linnehan pleaded guilty to conspiracy to distribute and possess with intent to distribute controlled substances.

Linnehan was one of 10 H-Block gang members and associates charged in August 2024 following a multi-year investigation of H-Block beginning in 2021 in response to an uptick in gang-related drug trafficking, shootings and violence. According to court documents, over 500 grams of cocaine, cocaine base (crack cocaine) and fentanyl, as well as over 20,000 doses of drug-laced paper were seized during the investigation.

The investigation of H Block began in response to an uptick in gang-related drug trafficking, shootings and violence. Since the start of the investigation in 2021, law enforcement attributed 12 incidents of gunfire to growing tensions involving H Block gang associates. Six H Block members and associates were arrested and charged with drug dealing in Boston and the surrounding communities. Four additional H Block members and associates were already in state custody at the time of the arrests. Additional drugs and four firearms were seized during the subsequent arrests.

From 2022 through 2023, Linnehan, a long-time H Block gang associate, participated in a conspiracy to distribute various controlled substances, in particular, fentanyl and cocaine. According to court filings, Linnehan was a supplier of fentanyl to his co-conspirators and also engaged in various drug deals with an undercover officer.

According to the charging documents, the H Block Street Gang is one of the most feared and influential city-wide gangs in Boston. Originally formed in the 1980s as the Humboldt Raiders in the Roxbury section of Boston, the gang re-emerged in the 2000s as H Block. Current members of H Block have a history of violent confrontation with law enforcement, including an incident in 2015 when a member shot a Boston Police officer at point blank range without warning or provocation.

Linnehan is the 6th defendant to be sentenced in the case.

United States Attorney Leah B. Foley; Jarod A. Forget, Special Agent in Charge of the Drug Enforcement Administration, New England Field Division; Randy Maloney, Special Agent in Charge of the U.S. Secret Service, Boston Field Office; Ted E., Docks, Special Agent in Charge of the Federal Bureau of Investigation, Boston Division; Boston Police Commissioner Michael Cox; and Russell W. Cunningham Special Agent in Charge of the Department of Justice Office of the Inspector General Mid-Atlantic Region made the announcement. The investigation was supported by the Massachusetts State Police; Suffolk County District Attorney's Office; Massachusetts Department of Corrections; and the Braintree, Quincy, Randolph, and Watertown Police Departments. Assistant United States Attorney John T. Dawley of the Organized Crime & Gang Unit and Jeremy Franker of the Justice Department's Violent Crime & Racketeering Section are prosecuting the cases.

The case was investigated under the Organized Crime Drug Enforcement Task Forces (OCDETF). OCDETF identifies, disrupts, and dismantles the highest-level criminal organizations that threaten the United States using a prosecutor-led, intelligence-driven, multi-agency approach. For more information about Organized Crime Drug Enforcement Task Forces, please visit Justice.gov/OCDETF.

The details contained in the charging documents are allegations. The remaining defendants are presumed innocent unless and until proven guilty beyond a reasonable doubt in a court of law.