The two male nurses who confessed to killing at least 16 Uruguayan hospital patients took advantage of emergencies to steal drugs that they then used to commit murder, officials said Tuesday. Deputy Health Minister Lionel Briozzo said at a press conference that health facilities normally keep records and control how medications are used for each patient. But \"when emergency cases intervene -- fairly common in intensive care centers -- such as cardiac arrest or massive bleeding, immediate resuscitation measures are started (and) control is set aside to address the importance of giving immediate medication to save a life,\" he said. The system for safeguarding medication did not fail, but \"persons who, instead of reviving people, were speculating about how to steal drugs to keep them and then kill other people,\" the deputy health minister said. Police arrested the two nurses on Sunday and charged them with murdering patients at a private Neurological Intensive Care Center and at a public hospital\'s intermediate-level care unit. The names of the suspects have not been released, but the El Observador newspaper identified them as Ariel Acevedo, 46, and Marcelo Pereira, 40. The men confessed to the killings, telling investigators \"they didn\'t like seeing people suffer,\" said Rolando Vomero, the judge overseeing the investigation. Health Minister Jorge Venegas described the suspects as \"serial killers,\" and promised far-reaching inspections of both private and public medical facilities, in consultation with the World Health Organization. They are suspected of injecting air into some patients intravenously, causing pulmonary embolisms and cardiac arrest, while others were injected with overdoses of anesthetics, a judicial source said.