Obama reassures US on terror threat

President Barack Obama sought Thursday to reassure Americans they face no "credible" terror threat, as US authorities began a review of the visa system that let one of the San Bernardino shooters into the country.

"At this moment, our intelligence and counterterrorism professionals do not have any specific and credible information about an attack on the homeland," the president said after meeting top US security officials at the National Counterterrorism Center in Virginia.

"That said, we have to be vigilant," he said.

The December 2 murder of 14 people in San Bernardino was carried out by US-born Syed Farook and his Pakistani wife Tashfeen Malik, reports AFP.

Obama repeated his pledge to hunt down IS in its stronghold in Syria.

The US president has also ordered a review of the K-1 visa system -- also known as the "fiancee visa" -- which Malik used to enter the United States. Possible changes include increased monitoring of social media posts and a more detailed background check and interview process.

An analysis by a California State University research group has found that hate crimes against Muslim Americans and mosques across the United States have tripled in the wake of the terrorist attacks in Paris and San Bernardino, California, with dozens occurring within just a month.

The spike includes assaults on hijab-wearing students; arsons and vandalism at mosques; and shootings and death threats at Islamic-owned businesses, reports New York Times.

"The terrorist attacks, coupled with the ubiquity of these anti-Muslim stereotypes seeping into the mainstream, have emboldened people to act upon this fear and anger," said Brian Levin, a criminologist at the university.