28-year-old Fasih, after being in detention for five months in Saudi Arabia, was taken into custody from Delhi airport on his arrival from the Gulf, official sources said.
India had sought deportation of Fasih from Saudi Arabia and also got an Interpol Red Corner notice issued against him.
An engineer and believed to be a member of the banned outfit Indian Mujahideen, Bihar-born Fasih is alleged to have been involved in the Chinnaswamy Stadium blast in Bangalore and the shooting near Jama Masjid (Delhi), both in 2010, and is wanted by Delhi and Karnataka police.
His name cropped up during the interrogation of suspected IM terrorists arrested during the last nine months.
While the Saudi authorities confirmed his detention there, they conveyed that they were closely examining his role and stay in that country.
Fasih's wife Nikhat Parveen had approached the Supreme Court claiming that her husband was in the custody of central security agencies, a charge denied by the Government.