unexplained aches and pains. Observed rate of psychological disturbances in Afghan refugees is equivalent to 0.22 per 1,000 persons. Legal issues Persecution and discrimination Afghans living in Pakistan are vulnerable to torture, persecution and mistreatment. They have often been targeted by Pakistani authorities. After the 2014 Peshawar school massacre by members of Tehrik-i-Taliban, the militants, all of whom were foreign nationals, comprising one Chechen, three Arabs and two Afghans, the government of Pakistan decided to deport tens of thousands of Afghan refugees. The strain on relations between Pakistan and Afghanistan and Afghanistan's relations with India have also contributed to anti-Afghan sentiment. Pakistanis claim that the influx of Afghan refugees since the 1980s has contributed to increased sectarian violence, drug trafficking, terrorism and organised crime in Pakistan. According to the Pakistan Citizenship Act 1951, people who migrated to Pakistan before 18 April 1951 (and their descendants) are Pakistani citizens. Although the act was directed at Muhajir settlers who arrived in Pakistan following the partition of India in 1947, it generally included all migrant groups (including Afghans). Those who immigrated after this date are required to apply for Pakistani citizenship and identity documents. It is estimated that over 200,000 Afghans who arrived after 1951 have obtained Pakistani citizenship and identity documents, such as Computerized National Identity Cards (CNICs), without formal applications. In 2015, Pakistani authorities pledged to invalidate the documents, making older Afghans illegal immigrants. National Database and Registration Authority and passport officials, union councils and political activists were found to have created fake identities and sell Pakistani national identity cards to Afghan migrants. Thousands of Afghans were reported in Pakistani jails in May 2011, most of whom were arrested for offenses ranging from petty crimes to not having a proof of registration (PoR) card, Pakistani visa or Afghan passport. In 2007, 337 Afghan nationals "were arrested for illegally travelling to Saudi Arabia to perform Hajj on fake Pakistani passports. After serving prison sentences and paying fines, they were released on "the condition they will not enter Pakistan illegally again." In 2012, 278 Afghan nationals were arrested by intelligence agencies for possessing fake Pakistani CNICs. According to the Khyber Pakhtunkhwa Home and Tribal Affairs Department, "A number of Afghan refugees (have) managed to obtain fake CNICs from different National Database and Registration Authority (NADRA) offices, especially from Zhob, Loralai, Bhakkar, Muzafargarh, Thatta and Dera Ismail Khan". Khyber Pakhtunkhwa officials said that action