A PRISON officer who sold 40 packets of cigarettes to an inmate for $2,000 was jailed for four months yesterday. Tang Chi-kwong, 30, a Correctional Services Department assistant officer who was attached to Ma Po Ping Prison, admitted the offence. Prisoner So Chi-keung, 25, was jailed for one month after admitting aiding and abetting a fellow inmate to offer the money to Tang. The sentence will be added to a five-year jail term for robbery passed in the District Court in May 1990. So was originally expected to be released from prison this August. Although Tang was described as a decent young man in a probation report, magistrate Mr Michael Hill said a deterrent sentence was called for. The court heard that Tang was in financial difficulties as a result of gambling and had asked So if he knew of any prisoner who wanted to buy 20 packets of cigarettes for $1,000. So approached a prisoner with Tang's suggestion and the inmate agreed to make the deal. Between May and June last year, Tang brought 40 packets of cigarettes into the prison and handed them over to So. At Tang's request, So told the prisoner to pay $2,000 into the bank account of Tang's girlfriend. The matter was later referred by the CSD to the Independent Commission Against Corruption.