Chungking Mansions building, located at 36-44 Nathan Road in Tsim Sha Tsui, is supposedly residential, it is made up of a labyrinth of hundreds low cost guesthouses, curry restaurants, African bistros, clothing shops, sari stores, and foreign exchange offices. It often acts as a large gathering place for some of the ethnic minorities in Hong Kong, particularly South Asians (Indians, Nepalese, Pakistanis, Bangladeshis and Sri Lankans), Middle Eastern people, Nigerians, Europeans, Americans, and many other peoples of the world. Chungking Mansions is 17 stories tall and consists of five blocks, A, B, C, D and E. There are two lifts in each block, one of which serves even-numbered floors, the other one odd-numbered floors. A CCTV camera system exists at the ground floor level for each of the lift cars. The first two floors are however common space where you can wander around under the blocks , the third floor is actually a terrace level between the blocks where the tower blocks rise out of the base of the building and all floors above this are accessible only by the stairways and lifts contained in each block. It is also known to be a centre of drugs, and a refuge for petty criminals, scammers, and illegal immigrants. 208 CCTVs were installed throughout the building in 2004 and under the central control of a security company. It also hires security guards and cleaning workers to patrol in the building day to night and ensure the cleanliness of the building respectively. From time to time, police officers and the immigration officers check the identity of the people inside this building in order to crackdown on drug-trafficking, overstaying and other criminal offences. With all these effort the security and environment in Chungking Mansions has been improving significantly.