The father of a 3-year-old British girl kidnapped at gunpoint last month by Nigerian militants has died, according to a spokesperson for the British Foreign Office. He apparently postponed needed medical treatment because of his daughter’s abduction. Mike Hill was a British expatriate oil worker living in the oil-rich Niger Delta region with his wife and their daughter, Margaret, when gunmen took the girl at gunpoint on her way to school. The captors warned the family they would kill the girl if her father did not swap places with her and pay a ransom. The girl was released unharmed two days later, and according to another Nigerian militant group who pressured the child’s captors, without any ransom being paid. THE BLOTTER RECOMMENDS Photos What’s Leading to Terror in the Niger Delta? Blotter Nigerian Militants Told Captors: Free Toddler or Else Blotter Nigerian Gang Threatens to Kill Toddler Hostage Click Here for Full Blotter Coverage. But British media reports say that because of the kidnapping, Hill postponed a trip back to the U.K. to receive medical treatment for kidney failure and has now died as a result. In the last three years, kidnap-for-cash has become an increasing problem in the Niger Delta. More than 150 foreign oil workers have been kidnapped in this year alone. In previous years, most of the kidnappings were undertaken by the organized militant group Movement to Emancipate the Niger Delta (MEND), or groups similar, who demand that the impoverished residents in the Niger Delta receive more of the billions of dollars of oil revenue. Click Here for Full Blotter Coverage. Jack Cloonan, an ABC News consultant and hostage negotiator, deals with kidnappings in Nigeria frequently. He says families of hostages are under enormous stress in any situation, but says Margaret Hill’s kidnapping was one of the more brazen acts he has seen. "Here’s a guy living off the economy, married to a Nigerian, and they take his kid," Cloonan said. "To target kids is as nasty as it gets." Do you have a tip for Brian Ross and the Investigative Team?