His family reportedly received terrorizing midnight phone calls while he was detained, saying Ghonim was being "taught a lesson."
Ghonim, Google's head of marketing for North Africa and the Middle East, was the highest profile detainee among the journalists and protesters who have been detained in Egypt. He had thrown himself into the growing uprising there, regularly updating his Twitter account on his experience, which were clearly moving him.
On his Twitter account, Ghonim wrote upon his release on Feb. 7 that "Freedom is a bless that deserves fighting for it." He later wrote "When you don't see anything but a black scene for 12 days you keep praying that those outside still remember you. Thanks everyone."
Ghonim credited his release to Dr. Hosam Badrawy, the newly named head of the ruling National Democratic Party in Egypt.
"Gave my 2 cents to Dr. Hosam Badrawy, who was reason why I am out today," Ghonim wrote on Twitter. "Asked him resign cause that's the only way I'll respect him."
Google also confirmed his release. "It is a huge relief that Wael Ghonim has been released," said a spokesperson via e-mail. "We send our best wishes to him and his family."
His disappearance on Jan. 28 had his readers on the edge with his ominous last Twitter post: "Pray for #Egypt. Very worried as it seems that government is planning a war crime tomorrow against people. We are all ready to die."
On Jan. 25, the day when major protests exploded, he mentions being with hundreds who were beaten by police. He marched to Tahrir square chanting, "Bread, freedom, dignity," and said he saw the crowd grow from 10,000 to 30,000 people.