Pakistani authorities have sealed off the offices of the international aid group Save the Children, saying the charity was "working against the country", police and government officials say.

Government officials accompanied by police arrived at the charity's office in the heart of the capital Islamabad on Thursday after working hours and placed a lock on the compound gate.

"We have sealed the office of Save the Children on government instructions," Kamran Cheema, a senior government official, told the AFP news agency.

"We don't know the reasons behind this order. We were sent a three-line notification by the interior ministry saying that this office should be sealed and all the expatriate staff be sent back to their countries within 15 days."

The government did not make any formal announcement but an official from the interior ministry told AFP that the agency was involved in "anti-Pakistan activities".

"Their activities were being monitored since a long time. They were doing something which was against Pakistan's interest," said the official without giving his name because he was not authorised to speak to the media.

Strong objection

A spokesperson for Save the Children confirmed in a statement that its office had been sealed off without warning.

"Save the Children was not served any notice to this effect. We strongly object to this action and are raising our serious concerns at the highest levels," the spokesperson said.

"Save the Children has worked in Pakistan for more than 35 years and we currently have 1,200 [Pakistani] staff members working across the nation.

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"All our work is designed and delivered in close collaboration with the government ministries across the country, and aims to strengthen public service delivery systems in health, nutrition, education and child welfare."

Al Jazeera's Kamal Hyder, reporting from Haripur in Pakistan, said on Friday that the suspicion against Save the Children started after the successful US mission to find al-Qaeda chief Osama bin Laden.

In 2012 a Pakistan intelligence report linked the aid group to Pakistani doctor Shakeel Afridi who was allegedly used by the CIA to carry out a fake vaccination programme as they searched for bin Laden.

The charity's expatriate staff were forced to leave Pakistan after the accusations emerged.

Save the Children has always denied it had any links with Afridi or the CIA.

Our correspondent said the crackdown on the charity have come amid government efforts to introduce stricter controls on nongovernmental organisations and charities through the legislature.

"There has been deep suspicion with the government that [these groups] have colluded with foreign powers," he said.

Source: Al Jazeera And AFP