U.S. authorities in Pakistan could have sought - but did not - a full background security investigation of San Bernardino shooter Tashfeen Malik before granting her a visa to enter the United States in 2014, according to a U.S. official familiar with the matter.<br />Under the U.S. "Visa Security Program," consular officials in American embassies overseas can ask U.S. Immigration and Customs Enforcement agents stationed in the embassies to produce a "Security Assessment Opinion," or SAO, before the consulate decides whether to approve a U.S. visa application.<br />It was the latest twist in the case of U.S.-born Syed Rizwan Farook, 28, his Pakistani-born wife, Malik, 29, who investigators said became radicalized long before they killed 14 people in a shooting rampage in San Bernardino, California, on Dec. 2.
