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All three suspects in a deadly bank robbery and hostage drama in Stockton, California, are members of one of the city’s most violent and entrenched gangs, the Nortenos, police tell NBC News.

While investigators are still trying to determine why the suspects allegedly ended up taking three hostages -- one of whom later died along with two of the three gunmen -- after robbing the bank on Wednesday, police spokesman Joe Silva said Thursday that the suspects came armed for a fight and were ready to mix it up with police at the slightest provocation.

"We don't exactly yet know their mindset" said Silva. "But they were ready to get in a gun battle if they thought police officers were going to intervene."

Silva declined to identify the gang, but at a later news conference police said it was the "Norteno" street gang.

Police in Stockton have been targeting the gang -- a local group affiliated with the dominant Latino gang in Northern California -- for years. In November 2012, police rounded up at least 39 members of the gang and seized weapons and narcotics, according to KCRA-TV, NBC's Sacramento affiliate.

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Police on Thursday identified the surviving gunman as 19-year-old Jaime Ramos of Stockton. They did not identify the other two men, but said they were 27-year-old and 30-year-old residents of Stockton.

Silva said that gang activity had risen significantly since 2008 when the city was hit with a series of "fiscal emergencies" that led it to declare Chapter 9 bankruptcy in June 2012.

He said police recovered numerous weapons, including three handguns and an assault-style semiautomatic rifle. He said the suspects also had loaded magazines strapped to their bodies, but could not immediately provide a total number of magazines or unfired bullets.

Under California law, possession of a semiautomatic assault rifle is illegal if it is equipped with certain generic features, including high-capacity magazines. Citing the unfolding investigation, Silva could not immediately say if the rifle was stolen, purchased outside the state or over the Internet.

Silva said police were still processing several crime scenes. After putting the number of rounds fired at about 100 on Wednesday, he now says he believe that “hundreds” of rounds were fired during the chase and final gun battle and that at least 14 patrol cars were "riddled with bullets."

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Stockton, which has a population of approximately 300,000, has been contending with a sharp rise in violent crime since it declared bankruptcy.

It set a record for homicides in 2011, when 58 slayings were reported, but saw that mark shattered the following year, when the number hit 71.

The murder rate dropped by half to 32 in 2013 as city leaders restored some funding cut as a result of the city’s financial crisis, bolstered the police department’s community-based policing program and formed partnerships with outside law enforcement agencies. Under Police Chief Eric Jones, the department has responded by partnering with other law enforcement agencies to target what Silva called “the worst of the worst” to keep the gangs at bay.

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Still, Stockton’s violent crime rate is high. The city recorded 4,630 violent crimes per 100,000 population in 2012, according to the FBI’s Uniform Crime Report. By comparison, San Jose, a city of nearly 1 million, recorded 3,547 violent crimes per 100,000 people that year.