Pakistan sent back more than half a million illegal immigrants, majority of them Afghans, since launching a crackdown against them last year, it emerged on Tuesday.

The interior ministry informed the Senate, the upper house of parliament, that those sent back were about one third of all unlawful immigrants living in the country, A written reply was submitted to the Senate by the ministry in response to a question by Senator Mohsin Aziz on the number of illegal residents in the country as well as the number of those deported.

The ministry said that around 1.7 million "illegal aliens" are unlawfully living in the country, the majority of whom are Afghans, who are living without any legal documentation necessary for staying in the country.

It further said that “541,210 people have been sent back after the cabinet’s approval of the deportation plan for illegal residents.” It added that nearly 1.15 million illegal aliens were still living in the country and continuous efforts were under way to identify and deport the remaining people.

It also said that 271,985 people were repatriated through the Khyber Pakhtunkhwa province and another 159,161 through Balochistan province. Both provinces share a border with Afghanistan.

It added that according to data from other systems such as the Integrated Border Management System, a further 110,064 had also left the country.

The government in October issued an ultimatum to all undocumented immigrants to leave Pakistan by Oct 31 and warned to launch a crackdown from Nov 1 against those who failed to follow those directives.

As the deadline ended, the government began a campaign to expel illegal foreign nationals.

As the majority of the illegal residents came from Afghanistan, the interim government in Kabul tried to get the orders reversed but without any success. Besides the Afghan government, the human rights bodies also criticized the government.

However, the government insisted that Afghan nationals were involved in terrorist activities and it was essential for the national security to expel the illegal residents and those interested to come back should come through legal channels.

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