Such accidents occur in the United States on a regular basis as the legislation in several states permits residents to keep a pistol. On December 2, the gunfire erupted in a conference room where the San Bernardino County Department of Public Health was holding a banquet.

A heavily armed man and woman terrorized the town. The couple was armed with 223-caliber assault rifles and semiautomatic handguns and was wearing combat clothes. This proves a careful planning to the assault. A third person seen fleeing from the scene of the shootout is in custody.

At least 14 people were killed and 17 people were heavily wounded during the mass shooting.

The police shot two suspects after a high-speed chase in a shootout hours later. The state authorities do not rule out a terror attack. With the investigation still unfolding, much is unclear about the deadly shooting, in particular motives of attackers.

They were identified as a man Syed Rizwan Farook, 28, and a woman, Tashfeen Malik, 27. The police found out that they were married. Besides, the young man is known to have settled in the US since childhood.

President Barack Obama was briefed by his homeland security adviser. In an interview with CBS News, Obama said US gun violence "has no parallel anywhere else in the world" and again called for "common-sense gun safety laws."

Importantly, the terror attack in San Bernardino has been the worst mass shooting in recent months. In October, 15 students were shot during the assault in a college.