country's 40,000 to 60,000 Buddhist monks, regarded by the regime as social parasites, were defrocked and forced to work in the rural co-operatives and irrigation projects. Many monks were executed; temples and pagodas were destroyed or turned into storehouses. Images of the Buddha were defaced and dumped into rivers and lakes. People who were discovered praying or expressing religious sentiments were often killed. The Christian and Muslim communities also were even more persecuted, as they were labelled as part of a pro-Western cosmopolitan sphere, hindering Cambodian culture and society. The Roman Catholic cathedral of Phnom Penh was completely razed. The Khmer Rouge forced Muslims to eat pork, which they regard as forbidden (ḥarām). Many of those who refused were killed. Christian clergy and Muslim imams were executed. One hundred and thirty Cham mosques were destroyed. Despite its ideological iconoclasm, many historical monuments were left undamaged by the Khmer Rouge; for Pol Pot's government, like its predecessors, the historic state of Angkor was a key point of reference. Ethnic minorities The Khmer Rouge banned by decree the existence of ethnic Chinese, Vietnamese, Muslim Cham, and 20 other minorities, which altogether constituted 15% of the population at the beginning of the Khmer Rouge's rule. Tens of thousands of Vietnamese were raped, mutilated, and murdered in regime-organised massacres. Most of the survivors fled to Vietnam. The Cham, a Muslim minority who are the descendants of migrants from the old state of Champa, were forced to adopt the Khmer language and customs. Their communities, which traditionally had existed apart from Khmer villages, were broken up. Forty thousand Cham were killed in two districts of Kampong Cham Province alone. Thai minorities living near the Thai border also were persecuted. The state of the Chinese Cambodians was described as "the worst disaster ever to befall any ethnic Chinese community in Southeast Asia". Cambodians of Chinese descent were massacred by the Khmer Rouge under the justification that they "used to exploit the Cambodian people". The Chinese were stereotyped as traders and moneylenders, and therefore were associated with capitalism. Among the Khmer, the Chinese were also resented for their lighter skin color and cultural differences. Hundreds of Chinese families were rounded up in 1978 and told that they were to be resettled, but were actually executed. At the beginning of the Khmer Rouge's rule in 1975, there were 425,000 ethnic Chinese in Cambodia. By the end in 1979,