Sahar Gul’s mother-in-law and sister-in-law were arrested and her husband was being sought, said interior ministry spokesman Sediq Sediqi.
The case has shocked Afghanistan. President Hamid Karzai has said that whoever used violence against Gul will be punished.
According to officials in north-eastern Baghlan province, the in-laws kept Ms Gul in a basement for six months, ripped her fingernails out, tortured her with hot irons and broke her fingers. Police freed her last week.
“It is a violent act that is unacceptable in the 21st century,” Mr Sediqi said. ”
Many Afghans prefer to go to India or Pakistan for care because of better medical services.
Ms Gul was married about seven months ago. Jawad Basharat, a police spokeman, said an arrest warrant had been issued for her husband, who is serving in the Afghan army.