“The visit was kept a secret due to security issues,” a relative said on condition of anonymity after Yousafzai was greeted at Benazir Bhutto International Airport in Islamabad by government and security officials. She was taken to a hotel under high security, the relative said.

Yousafzai will reunite with all of her family in Islamabad during the four-day visit, but she won’t visit Swat because of the concerns for her safety, relatives said. She is scheduled to meet with Prime Minister Shahid Khaqan Abbasi and other government officials later on Thursday.

Yousafzai had already won international acclaim as an advocate for women’s education when she caught the attention of the Taliban, which had gained a stronghold in the Swat Valley. On Oct. 9, 2012, a gunman stormed her school bus in Mingora and shot her in the face at point-blank range to silence her. She was critically wounded but recovered at a hospital in Britain.

Since then, she has become a worldwide symbol of female empowerment, founding the Malala Fund, a charity dedicated to giving all girls access to education, with her father, Ziauddin.

Yousafzai told David Letterman in a recent episode of his Netflix interview series that she had been searching for an opportunity to return to Pakistan.

“I want my feet to touch that land and to be there,” she said.