ISLAMABAD, JAN 22, SPA -- More than 1.6 million Afghan citizens have been registered so far in the largest registration exercise conducted by the Pakistan government in collaboration with the UN refugee agency, officials said. Registered Afghans received Proof of Registration cards valid for three years that recognize the bearers as Afghan citizens temporarily living in Pakistan. Those who took part in the 2005 census but whose names are not in the census database have been asked to approach the registration centers in their areas. The government has also announced that the registration of Afghan citizens will be extended till February 2.--SPA www.spa.gov.sa/419869