The Christian human rights lawyer who disappeared into police custody in China, arousing fears for his safety, has been released.
Zhang Kai is now back with his parents and northern Inner Mongolia.
Kai, who has worked with Christian pastors protesting China's cross removal programme, was summoned him to his local police station on 27 December.
His sister, Zhang Yan, told sources working with the Christian charity China Aid that he often receives these summons.
He is currently still on bail after a previous detention.
However, the family was particularly concerned this time because he was held for 48 hours.
His plight once again aroused international attention after his mother called drew attention to the case through online media.
One social media user speculated: "They might do something like they did to Yang Hua and frame him with something involving state secrets and use this as a means to arrest him."
Zhang Yan said her brother had been trying to stay out of trouble and spent his time reading and taking care of his fish.
Kai was originally imprisoned in 2015 and then released on bail earlier this year after he "confessd" on television to disturbing public order and endangering state secrets.
He was ordered to return to a police station in Hohhot, Inner Mongolia on 27 December. He was taken into custody and both his mother and sister then received visits from securty officials who told them his release depended on his willingness to cooperate.
His mother told China Aid that security services had been to her and her daughter's homes to have a "conversation". She said at the time: "They urged us to persuade Zhang Kai to keep quiet and cooperate with them. Whether Zhang Kai can go home or not depends on his attitude.
"Our family is in the midst of waiting anxiously. I hope Zhang Kai returns safely. Please pay urgent attention."
Bob Fu, founder and president of China Aid and a friend of Zhang, has described him as a "bold human rights lawyer".
China Aid exposes abuses, such as those suffered by Zhang Kai, in order to promote religious freedom, human rights, and rule of law.