The Pakistani government shut down the offices of Save the Children in Islamabad without giving any reason, officials said Friday.

Pakistani officials placed a lock on the gate of the international aid group’s officers Thursday night and asked employees to leave.

The officials also told Pakistani employees that the government wanted all foreign nationals working with the charity group to leave the country within the next 15 days. It is unclear how many foreigners were working with Save the Children in Pakistan.

Two government officials said the action was taken on orders from the Ministry of Interior. They were not authorized to speak to the media.

Qazi Khalilullah, the spokesman for the Foreign Ministry, did not answer any questions regarding the matter. He referred any inquiries to the Ministry of the Interior.

"I will not be commenting on a decision that has been taken by the government. Our decisions are always well considered," he said during a weekly news briefing on Friday.

The organization responded to the abrupt shutdown in a statement released Friday.

"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," it said, added that the group has worked in Pakistan for over 35 years and that currently it had 1,200 employees nationwide-- none of them a foreign national.

The group's programs in health, education and food security reached more than 4 million children and their families last year, it said.

"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," it said.

Save the Children has previously been accused by Pakistani intelligence agencies of facilitating a Pakistani doctor's vaccinations program in the city of Abbottabad as cover for the CIA to obtain DNA samples at a compound where Al Qaeda leader Usama bin Laden was later killed by U.S. commandos.

The Associated Press contributed to this report