At least 27 American citizens, including five U.S. servicemen and 22 private businessmen and contractors, are being held hostage by militant groups worldwide, an ABCNews.com analysis has found. And the fate of many of them has received little attention since their kidnappings. The U.S. State Department does not officially report the number of missing Americans civilians. Nineteen of the Americans held hostage are in Iraq, including the three soldiers who are believed to have been captured last week. Five other Americans have been reported kidnapped by militant groups in Nigeria, and three more have been held by the Colombia terror group FARC for the last four years. "It’s a growth industry," says Jack Cloonan, an ABC News consultant and former FBI agent who now runs a firm specializing in negotiating the release of hostages. "If you’re a large multinational company or doing business in iffy places, you are at risk." Photos: See the Faces of America’s Missing The three American contractors held in Colombia were flying a drug surveillance plane for the U.S. military when it crashed in February 2003. FARC has posted photos of Keith Stansell, Marc Gonsalves and Thomas Howes. A Colombian police officer, who escaped last week after being held hostage by FARC for eight years, says the three Americans are alive but are suffering from malnutrition. One hostage has hepatitis. Click Here for Full Blotter Coverage. In a statement released to the Blotter on ABC News.com, Northrop Grumman, the contracting firm for which the men work, says the company is "pleased to learn last week of this new indication of proof-of-life for our three coworkers who have been held captive by the FARC for more than four years in Colombia. However, we are deeply concerned about news reports of a possible health issue involving one of our employees. We hope and request proper and adequate medical care be provided to Marc Gonsalves as well as Tom Howes, Keith Stansell and all the other hostages. Northrop Grumman continues to work with various agencies and departments of the U.S. government and others on efforts to secure the safe, timely release of all three employees." Negotiations to free the men have been stalled as it is U.S. policy not to negotiate with groups labeled as terrorists. In Nigeria, five Americans are being held in the oil-rich Niger Delta region by two different militant groups. One American, John Stapleton, has been held for three weeks by the group MEND (Movement for the Emancipation of the Niger Delta) after being captured during a raid on a Chevron facility. In an e-mail to the Blotter on ABCNews.com, the group’s leader, Jomo, says Stapleton is in good health but won’t be released until May 30 to "spite the outgoing [Nigerian] administration which will be leaving office on the 29th of May." The four other Americans in Nigeria are being held by a militant group that calls itself the Niger Delta Freedom Fighers (Egbema One). The men are employees of Global Industries, a Nigerian-based oil servicing company that works with Chevron. According to Nigerian media reports, the hostages, Mike Roussel, Chris Gay, Larry Plake and Kevin Faller, who have been in captivity for almost two weeks are in good health, but the kidnappers are demanding more political clout for their tribe and better sharing of oil revenue before the men will be released. Cloonan says it’s harder to negotiate for hostages when the kidnapping is politically motivated rather than financially motivated. "At the end of the day, it’s still a business," he says. "It’s not just paying a ransom. You really have to know how to negotiate, and you have to know how the time line is going to work." The 19 missing Americans in Iraq include five servicemen and 14 government contractors and civilians. Little has been heard about any of them since their capture, leading to fears about their prospects for release. Jeffrey Ake, an Indiana businessman has been a hostage in Iraq for more than two years. He was captured in 2005 outside a bottling plant his water-distribution company was building. A tape appeared on the al Jazeera network two days after his disappearance, but he has not been heard from since. FBI officials have said they still classify him as missing and have no reason to believe he is dead. Also among the missing are four American contractors, John Young, Jonathon Cote, Paul Reuben and Josh Munz, who were kidnapped in an ambush in southern Iraq last November. In January 2007, their captors released a videotape of the men where they are heard pleading for the United States to get out of Iraq. Nothing has been heard since. Cloonan says Iraq presents a special and unique problem for hostage negotiators. "Contractors who are working in Iraq, U.S. citizens, are the top of the pecking order," he says. "They are worth huge amounts of money and, coupled with that, are the political statements." Cloonan says someone kidnapped in Iraq is better off being captured by a Shiite group or former Baathist police officers who want money. "If you’re kidnapped by Sunni extremists who want to make a political statement," says Cloonan, "you are more likely to be killed." The State Department Web site states, "It is U.S. government policy to deny hostage takers the benefits of ransom, prisoner releases, policy changes, or other acts of concession." But the site also states the government "will make every effort, including contact with representatives of the captors, to obtain the release of hostages without making concessions to the hostage takers."