BOSTON — A roundup of suspects affiliated with Boston’s largest and most-feared gang included a man who was in charge of the group’s Portland drug operation, according to federal authorities.

More than 40 people were arrested Thursday on drug and gun charges as part of a crackdown on the Columbia Point Dawgs, a gang based out of Dorchester, Massachusetts, that has been involved in a bloody shooting war with rival gangs, according to papers filed with the U.S. District Court in Boston.

Officials said at a news conference that a grand jury indicted 48 members and associates of the criminal organization, which they said ran a vast drug empire that stoked New England’s heroin epidemic. Forty-one were arrested and seven remained at large.

The gang started operating out of the Columbia Point housing project in the Dorchester section of Boston in the 1980s, eventually trafficking drugs from Boston to Maine, authorities said.

The gang’s infiltration of drug trafficking territories held by rival gangs led to numerous killings, according to law enforcement officials. They cited the 1990s killing of a member who was shot while sitting in Whitney Houston’s Bentley with her husband, Bobby Brown.

A rival gang member was convicted.

Since 2010, the group, known on the street as “the Point,” has been considered the most powerful gang in Boston, U.S. Attorney Carmen Ortiz said. She said the gang was largely run by four families. Members of each of the families were among those indicted Thursday.

The gang expanded its drug trafficking business through southern Massachusetts, New Hampshire and Maine, according to an affidavit written by FBI Special Agent Matthew Knight.

“Demetrius and Yancey Williams’ crew operated a lucrative drug trafficking business throughout Boston and ran a drug pipeline between Boston and Portland, Maine,” the affidavit said referring to two of the people who were targets of the indictment. Their father was Yancey Calhoun, also known as “Pops,” a longtime CPD member, who “oversaw the Portland, Maine, branch of the Williams Crews’ drug operation.”

Calhoun was charged with conspiracy to distribute cocaine, crack cocaine and heroin, and aiding and abetting the conspiracy.

As the drug business grew, members of the gang promoted the gang’s notoriety by creating record labels under the names “8 Bus Records” and the “Waterboyz.” The FBI said the gang used the record labels to promote rap shows, occasionally demanding that visiting artists pay “protection fees” to perform in Boston. They also produced videos showcasing their luxury vehicles, expensive jewelry and guns.

Vincent Lisi, special agent in charge of the Boston FBI office, said authorities believe the gang has contributed to the heroin epidemic the region has been grappling with for the past few years. Authorities said the gang sold large quantities of heroin, cocaine, crack and oxycodone throughout Boston and Maine.

Boston police Commissioner William Evans said many of the gang members are well known to police and have been driving violence in the city in recent years.

During the last 18 months, the gang has been in a war with the Greenwood Street Posse, resulting in numerous shootings, prosecutors said.

“This is going to go a long way to making our streets safer in the city of Boston,” Evans said.

That bloody feud started last June when Columbia Point gang members were shooting at a member of another group, the Norfolk Street Bulls, in a dispute related to the rap business, but accidentally shot a member of the Greenwood Street Posse, court papers said.

The FBI executed 27 search warrants and has seized a kilogram of heroin, 200 grams of cocaine, 100 grams of crack cocaine, $1.5 million and 34 guns over the course of the investigation as well as three Mercedes Benz, a Maserati and Nissan Altima.