After spending more than 13 years in Guantanamo Bay, prisoner Shaker Aamer is being reunited with his family in the United Kingdom on Friday.

The Washington Post reports 46-year-old Aamer touched down at the Biggin Hill airport in his hometown of London Friday afternoon local time, much to the celebration of relatives and activists who called for his release.

A former British resident and Saudi national, Aamer was originally cleared for release in 2007. Congress confirmed that he would be transferred to the U.K. in September, making him the last British resident or citizen to be released from the U.S. prison in Cuba.

A spokeswoman for the British government said there were no plans to detain Aamer. According to the spokeswoman, Prime Minister David Cameron "welcomes his release and that people should be reassured that everything necessary to ensure public safety -- those measures have been put in place."

Aamer was captured by bounty hunters in Afghanistan in 2001. He was brought to Guantanamo Bay on suspicion of aiding terrorist Osama Bin Laden. Aamer allegedly confessed to the allegations, although family and supporters say he traveled to the country to do charity work.

No evidence was presented, and Aamer never received a proper trail. The human rights organization Reprieve claims the confession was forced under torture.

Aamer's wife and four children live in London. In 2005, his then 7-year-old daughter Johina wrote a letter to British officials requesting her father's release.

"He used to love me when he was with us all," she wrote, according to CNN. "We are all sad and depressed. We used to cry a lot for him. Sometimes my mum cries a lot on her bed or on her chair and on the floor and I don't know how to stop her. She used to cry then I cried."

"I want my father back tomorrow," Johina added.

Cori Crider of Reprieve was pleased to see Aamer finally released.

"It is long, long past time," Crider said. "Shaker now needs to see a doctor, and then get to spend time alone with his family as soon as possible."