Updated

A Boston City Hall employee and a man convicted of killing a local police officer 45 years ago were among 29 people charged as part of an undercover sweep targeting drug and gun crimes, the Justice Department announced Thursday.

Prosecutors said those arrested have been charged with state and federal drug, firearms and counterfeiting crimes.

One of those charged is Gary Webster, a project manager for the Boston Planning & Development Agency and the former director of constituent outreach for City Councilor Michelle Wu.

Investigators say Webster sold cocaine and fentanyl in 2016 to buyers who were secretly working with authorities.

In a statement, Wu said she was "saddened" at the news that Webster had been charged. She noted that Webster "has not worked in my office for over a year, [but] was part of my team when I first took office."

According to Webster's LinkedIn page, he began working in Wu's office in January 2014. The page did not indicate if or when he left that position.

Gary Webster 720

Gary Webster. (U.S. Attorney's Office-District of Massachusetts)

Webster has been placed on unpaid administrative leave.

Another one of the 29 charged is Terrell Walker, who was convicted of manslaughter in the 1973 killing of Boston police officer John Schroeder. Walker is now charged with unlawful possession of a firearm and other offenses.

It wasn't immediately clear if Walker has an attorney.

According to U.S. Attorney Andrew Lelling, the sting involved 130 co-called "controlled drug buys," mostly of heroin and fentanyl.

The Boston Herald reported that 23 charged individuals were arrested in connection with the investigation. Another four were already in custody and two others remain fugitives.

The Associated Press contributed to this report.

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