Russian investigators said Wednesday they had found narcotics on a Greenpeace ship whose crew was detained in the Arctic last month -- an allegation quickly disputed by Greenpeace as a smear. Some of the 30 people who were aboard the icebreaker Arctic Sunrise are likely to face additional charges, the Russian Investigative Committee said. Authorities say they think the narcotics include opium. The 28 Greenpeace activists and two journalists who were arrested on the ship as they protested Arctic drilling already face piracy charges. All 30 pleaded not guilty in court last week. The Investigative Committee said Russian experts were looking into the "origin and purpose" of the drugs seized, which it described as "presumably opium straw and morphine."