OAKLAND — Eighteen suspected members and associates of a violent East Oakland gang were arrested in a series of raids Tuesday morning throughout the Bay Area as part of the continuing Ceasefire operation, police said.

Seven guns were seized as well, police said at a news conference.

Tuesday’s raids in Oakland, Hayward, San Lorenzo, Antioch, Dublin, Stockton, Tracy and Sacramento bring to 30 the number of arrests made in the last several weeks as part of the police investigation of the gang. A total of 25 guns have been seized.

The majority of those arrested are men but there were also some women, authorities said.

They have been arrested as suspects in crimes ranging from murder to assaults with firearms to robberies, drugs and weapon possession, authorities said.

All are either members of associates of the Case Gang, a group with a violent history that recently has been involved in an “uptick” of bloodshed, including suspected involvement in two recent East Oakland homicides, Capt. Ersie Joyner III, said.

The raids were led by Oakland police who were assisted by the FBI, U.S. Marshals, the Alameda County District Attorney’s Office and police from the different cities where they occurred as well as other law enforcement agencies. SWAT teams from the different agencies were involved in the raids.

Joyner, who commands the department’s Ceasefire operation, said some of those arrested Tuesday were among the most violent and at “risk of jail and death.”

He said as part of Ceasefire they had been contacted by a group of law enforcement, clergy and the community and asked to stop the violence and warned if they did not they would face consequences.

“Some listened and some didn’t,” Joyner said. “Those who ignored the fair warning were held accountable.”

Chief of Police Sean Whent said Case Gang’s link to violence pretty much “self selected” itself for police scrutiny like Ceasefire.

Whent said nonfatal shootings in the city are down 15 percent this year which he said Ceasefire has played a key role in accomplishing. “You can see the strategy can work. We need to stay with it.”

Mayor Libby Schaaf said strategies like Ceasefire makes the message clear that “we will not tolerate violence and we value human life. We are serious about ending the violence.”

Police did two similar Ceasefire raids where arrests were made last month of suspected gang members in East and West Oakland.