By Mark Abrams

PHILADELPHIA (CBS) — Philadelphia District Attorney Larry Krasner is going after 10 big pharmaceutical companies alleging their marketing practices have contributed to the opioid crisis.

The district attorney says a team of outside lawyers – many of them working for free – did extensive research and helped his office prepare the suit against the big names behind prescription opioids.

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“Big pharma, we’re coming for ya! Make no mistake,” Krasner said during a Thursday afternoon news conference at his office. “It isn’t just gonna be the kids on the corners. It’s going to be big pharma, it’s going to be doctors, it’s going to be pain centers, it’s going to be pharmacies, and to the extent we have any opportunity, it’s going to be distributors who think that money is more important than lives.”

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Among the companies sued: Purdue Pharma, Cephalon, Teva, Endo Health, and Johnson & Johnson.

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Krasner says he’s seeking monetary damages to recover the costs paid by the city to deal with the opioid epidemic.