Two Indian businessmen were robbed of US$200,000 (HK$1.56 million) in cash after being pistol-whipped and tied up at gunpoint by two men in a Tsim Sha Tsui guesthouse yesterday. The pair, who arrived in Hong Kong on Thursday, were sleeping in a room at the fifth-floor guesthouse in Chungking Mansions, Nathan Road, when the robbers, believed to be mainland men, knocked on the door at 4am. 'When the victims answered the door, one of the robbers threatened them with what appeared to be a pistol. They were pistol-whipped before being tied up with tape. No shots were fired in the incident,' police said. The two raiders escaped with hand luggage containing the banknotes and apparently fled down a rear staircase, where the empty luggage was discovered. The police were called about 15 minutes later when the victims managed to free themselves. Heavily armed officers wearing bulletproof vests searched the building and checked all the guesthouses but found no trace of the two robbers. The two Indian men were taken to Queen Elizabeth Hospital, where they were treated for head injuries and discharged. The businessmen had intended to buy mobile phones and take them back to India. Officers were checking closed-circuit TV footage from the building's ground-floor lobby and lifts last night.