[2] In 2011, Hằng protested in Hanoi and in Ho Chi Minh City against Chinese territorial claims on the Spratly and Paracel Islands.
She was then arrested by police before been sent to Thanh Ha Education Center, a re-education camp in Vĩnh Phúc Province.
[4] In 2012, Hằng was freed and returned to her work on human rights, writing about her time in the Thanh Ha Education Center.
She also published a “Manual for the Implementation of Human Rights” (Cam nang thuc thi quyen lam nguoi).
[4] In 2016, Amnesty International reported Hằng had health problems in prison and she did not receive any medical care from the Vietnamese authorities.