Police are still trying to pinpoint the whereabouts of Obi Sr, who runs an inter-state transport company, after he failed to return home from work in Jos, the capital of the central Plateau state. Calls to his mobile telephone went unanswered before the device became unreachable on Saturday and, while no ransom demands have as yet been received, police believe that he has been kidnapped. Mikel was informed of his father's disappearance by André Villas-Boas, the Chelsea manager, on Saturday morning and opted to play in Sunday's Premier League game at Stoke City. Indeed, he relayed the news to one of his team-mates, Salomon Kalou, just before completing 90 minutes of the goalless draw at the Britannia Stadium.
The 24-year-old has now issued a public appeal for his father's release. "I just want to say to whoever has got my dad, please just let him go," he said. "He's just an old man, he hasn't done any harm to anyone as far as I know, so I don't know why he has been taken. My family, and my mum especially, are very sad and frustrated about this situation.
"There has been no communication from the abductors. Not at this point. We have not heard anything yet. I really don't have any idea about who might have taken him away. All I can say is, I am from Nigeria, and I have always tried to help my country in every way that I can. Playing for the country, serving the country, in every way that I can. And I think this is the time for the country to help me. So I'm just going to say, whoever has got my dad, whoever knows where he is, please can they contact me, and hopefully he will be released."
Dipo Ayeni, the Plateau state police commissioner, said the authorities are "still searching to find Mr Obi's location", with Mikel confirming he would remain in London, and available for selection, while the search continued around Jos.
Villas-Boas spoke with his player after the team's training session ahead of the trip to the Potteries and informed him of the situation. "The manager felt he had to tell me," Mikel said. "He told me everything, so I was kind of shocked. And he asked me if I still wanted to go to the game and play, and I said I wanted to. I would not want to let my team down, my club down. My family as well.
"It was really difficult, but if I had not played that game my mum would have been very sad with me. I spoke to her before the game and she told me to go out there and be strong and do everything that I can to help the club and to make sure I do well in the game.
"I don't think my team-mates really know about it. I told Didier Drogba today [Monday] and, before the game, I told Kalou, who is a very good friend of mine. I didn't want everyone coming to me and saying: 'Sorry, Mikel.' I just wanted to get on with the game."
John Ola Shittu, Mikel's agent, said: "It's been tough for the young man. The family in Jos reported [Obi Sr] missing at the police station, but we're taking all necessary measures to find him. We've told John to be brave and to stay calm. He is totally devastated. We were not sure whether to tell him before the game. But after speaking to the manager [André Villas-Boas], and [the Chelsea sporting director] Mike Emenalo, we agreed that he had a right to be informed of such a serious incident. He was under a lot of stress, but he showed a lot of character and mental strength to play against Stoke."
Kidnappings in Plateau state are a rarity when compared to Nigeria's oil-rich southern delta, where militants and criminal gangs often abduct foreigners for ransom – middle-class Nigerian families also increasingly find themselves targeted in the country's eastern provinces – and, in July 2008, the elder brother of the Everton defender Joseph Yobo, Nornu, was abducted in Port Harcourt. He was released 12 days later though it remains unclear whether a ransom was paid.
Police are now working on the assumption that Obi Sr was targeted given his high-profile and wealthy son. "They will definitely know who he is," Mikel said. "I was born in Jos, I grew up there, my family have lived there all our lives. They will definitely know who my dad is, and who his son is. But it is very rare for this to happen in Jos. It's normally a very safe place to live. This is a surprise to everyone."
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