Thirty people are facing charges today in a crackdown on two street gangs who terrorized residents in the Bowdoin-Geneva section of Dorchester and the Uphams Corner section of Roxbury, federal prosecutors said this afternoon.
“This community has been in desperate need of reprieve from the violence. We hope the arrests and prosecution of the defendants will quiet the streets and improve the quality of life for all residents,’’ US Attorney Carmen Ortiz said in a statement.
More than 300 federal, state, and local law enforcement officers made arrests and executed search warrants early this morning in what officials dubbed Operation Concord, which focused on violence and drug distribution by the Woodward Avenue and Hendry Street gangs, prosecutors said.
Mayor Thomas M. Menino called it “a great day for the hardworking people of Bowdoin-Geneva and Uphams Corner.’’
A total of 27 people were arrested — 25 locally, one in California and one in Maine. Two other defendants were already in custody and one person remains a fugitive. Twelve places were searched, prosecutors said.
The probe involved controlled drug buys, purchases, surveillance, and a wiretap. It began in the summer of 2011.
The defendants allegedly were involved in gang, gun, and drug activity. They were directed by Alexis Hidalgo, 31, of Dorchester, alleged leader of the Hendry Street gang, and Jonathan DaSilva, 29, of Roxbury, alleged leader of the Woodward Avenue gang, prosecutors said.
The gang leaders allegedly were responsible for distribution of large amounts of crack cocaine, oxycodone pills, and marijuana.
A woman standing at the intersection of Langdon and George streets in Roxbury, about 20 feet away from the scene of one of the raids, identified herself as DaSilva’s aunt, and expressed shock that he was arrested.
“That’s nonsense. He hasn’t done anything wrong,’’ said the woman, who declined to give her name because she feared repercussions from law enforcement.
Hidalgo and DaSilva were among nine people who made initial appearances before US Magistrate Judge Robert B. Collings this afternoon. The courtroom was packed with friends and relatives of the defendants.
When Collings asked the nine defendants whether they could afford their own attorney, only Hidalgo answered “Yes.’’
The defendants all bore expressions of exasperation or bewilderment on their faces, and most were shabbily dressed, indicating that they had very little time to prepare themselves during and after the raids.
As Cummings read out the charges against Hidalgo, the defendant, wearing a baggy white T-shirt and jeans, shook his head from side to side.
Another defendant abruptly stood up and asked Collings why was he being held when he had never been charged of any crime before. Collings responded that by virtue of the federal charges facing him now, the government has a legal right to hold him temporarily.
All of the defendants were held without bail. They are scheduled to return to court on Tuesday to be assigned attorneys, and to schedule a date for a detention hearing.
Another of the defendants in the case, Julio Collazo, made legal history in Massachusetts when he was among the first wave of teenagers accused of murder to be tried and convicted in an adult court. Collazo was 17 years old when he and Byron Alexander stabbed Glenn Louise to death on Cunard Street in Roxbury on May 13, 1997. Collazo wrapped up his manslaughter conviction in December 2011.
The Rev. Richard “Doc’’ Conway, a Dorchester Catholic priest whose parish includes some of the streets affected, said he was relieved to hear police had moved to arrest violent gang members from the area.
“Any time you get guns off the streets that’s a plus,’’ he said. “And when you cut down rivalries between gangs and get the leaders off the street, that’s good for the neighborhood.’’
Emmett Folgert, who runs the Dorchester Youth Collaborative in Fields Corner, said busting up two major gangs could have a ripple effect on smaller groups that often take their cues from older gang leaders.
He pointed to a homicide on Geneva Avenue last fall and a near-fatal shooting on Olney Street that followed immediately, both of which were linked to rivalries between two gangs.
Major arrests of gang leaders impact “not only the areas that these guys were operating out of but areas where their rivals are,’’ Folgert said. “It turns the temperature down. It’s a multiplier effect.’’