The Federal Bureau of Investigation (FBI) team, probing the California shootings in which the killer couple shot dead 14 people, revealed that the shooters Rizwan Farook and Tashfeen Malik have been radicalised for a long time.
The FBI team revealed that the duo had been having practicing sessions at a target range days before they carried out the dastardly act.
Initially, the investigation team was under the impression that Farook was convinced to carry out the attack by Malik who had declared allegiance to the Islamic State in one of her Facebook posts.
The authorities have also claimed that they have evidence that suggest that the couple have been planning the act for a long time and have been doing target practices.
Although the motives behind the murder are yet to be established, investigations reveal that Farook had ascribed to militant views much before he met his partner.
Though the FBI officials tried to confirm reports that Malik was associated with Islamabad's Red Mosque which is notorious for its fundamentalist views, the Mosque authorities denied having any sort of connections with her.
The FBI team has, so far, interviewed as many as 400 people. The officials are yet to chance upon any evidence that suggest that forces overseas had any role in the attack.