Muhammad Heykal Rahman had been a CNB officer for nearly a decade when he lied under oath. SINGAPORE: A sergeant with the Central Narcotics Bureau (CNB) lied under oath to cover up for his colleague, who was on trial for assaulting a man to extort a confession for drug offences. The officer who lied, Muhammad Heykal Rahman, 36, was jailed for one-and-a-half years on Monday (Dec 23) after pleading guilty to a charge of intentionally giving false evidence. Another charge of giving an