BRENTWOOD, N.Y. (CBSNewYork) — A week after a major gang roundup, Suffolk police have pledged to take things several steps further.

As CBS2’s Jennifer McLogan reported, on the streets of Brentwood a police drill sent a chilling message to gang members and gang wannabees.

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“If you are an MS-13 gang member, take a look behind me. For every person here there are ten more and we are coming for you,” Suffolk Police Commissioner, Timothy Sini said.

It was a powerful show of force — choppers were overhead, K-9 units were on the ground, and a phalanx of law enforcement from multiple Suffolk county gang fighting units pledged to stand behind a suffering community of school children and parents in Brentwood.

“The savages who murdered Kayla and Nisa are now behind bars, but it’s important to emphasize the job is not done,” Sini said.

Best friends and teenage girls Kayla Cuevas and Nisa Mickens were killed in September by a group of gang members who were allegedly armed with baseball bats and machetes.

Last week — following a six month investigation — more than a dozen suspects were rounded up. Most had arrived recently from Central America — steeped in the extreme gang violence of their homeland, prosecutors said.

Authorities said gang members found a niche in communities where a mounting turf war and peer pressure has taken hold of vulnerable kids.

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“We want you to pull away from these gangs. We don’t want this life for you,” Suffolk County Executive, Steve Bellone said.

The victims’ families said their daughters didn’t want that life either — which led to disputes on social media.

They were senselessly targeted as retribution.

“I am sure that Kayla is up in heaven and watching us down here. She would be wanting the police department doing everything that they can do to eradicate these individuals, and making sure our streets are safe,” Kayla’s mother Evelyn Rodriguez said.

Monica Martinez, now a legislator, was the victims’ school administrator.

“We need to make sure that our children live in a world where they can feel safe and loved where they can go in their front yard and throw a ball around,” she said.

Neighborhood meetings among police parents and students began this week.

In the six months since Cueva and Mickens were murdered, police said they have made 135 gang arrests.

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