But she confirmed that applications to be sent back home by eight other Nigerian prisoners in Hong Kong were rejected because the two governments were unable to reach 'satisfactory' arrangements or a 'consensus'.

The revelation re-ignited concerns that Olusanmokun - who also tried to jump bail before being charged and had a bid for diplomatic immunity rejected - has been given preferential treatment. It has also raised fears over whether he is actually serving the rest of his term in Nigeria.

Under the Transfer of Sentenced Persons Ordinance, both jurisdictions are required to swap 'relevant information' to ensure the sentence is being completed, but officials in the SAR have refused to say if they have done so.

Frontier legislator Emily Lau Wai-hing said she had received a complaint from a Nigerian prisoner trying unsuccessfully to be transferred for years.

She said he was furious after reading the Post's original story about Olusanmokun. Ms Lau has passed the complaint to Mrs Ip but has not had a reply.

'I am very concerned,' she said last night. 'If someone has had preferential treatment because of his status, this is very worrying. The Hong Kong Government should explain, otherwise it will be very embarrassing for them.'

Olusanmokun - the son of Nigeria's Consul-General, Ebenezer Olusanmokun - was jailed by District Court judge Fergal Sweeney on September 17. He was found guilty of possessing a stun gun and wounding off-duty police Chief Inspector Michael Armstrong at the Devil's Advocate bar in Wan Chai last February.

Last month, the Sunday Morning Post reported that on December 1 he was transferred from Tung Tau Prison to Nigeria to serve the rest of his sentence under an ad hoc arrangement between the Hong Kong and Nigerian governments under the Transfer of Sentenced Persons Ordinance. Hong Kong has no transfer-of-prisoners agreement with Nigeria.

The transfer has never been officially confirmed and the Government will not even reveal whether Olusanmokun is the prisoner involved, although the Post has confirmed this with reliable sources.

Independent legislator Bernard Chan tabled questions in Legco last week about the matter but Mrs Ip refused to comment on any individual cases.

Yesterday, Olusanmokun's father said he was aware of the other eight cases but could not comment until tomorrow. When asked if his son was in custody in Nigeria, he would only say: 'I don't know anything about that.'

Alan Crawley, of the Prisoners' Friends' Association, said other Nigerian inmates who had applied for a transfer were furious.

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