Updated

Two senior Pakistani security officials say that authorities have asked 21 foreign aid groups to wrap up their activities and prepare to leave Pakistan after they failed to re-register under a regulation introduced two years ago.

The officials say the international non-government organizations in question were told about the decision this week. They spoke on condition of anonymity because they are not authorizes to speak to reporters.

Pakistan unveiled tough registration rules in 2015 amid widespread suspicion that employees of aid groups engaged in spying.

There was no immediate comment from the aid groups.

Islamabad had been closely monitoring aid groups after arresting a Pakistani doctor, Shakil Afridi, who ran a fake vaccination campaign in Abbottabad as a front for a CIA-led effort to find al-Qaida leader Osama bin Laden.