Washington, Nov 17 (IANS): The US State Department subjects Syrian refugees to the most intensive security checks of immigrants as concerns raised after the deadly Paris attacks that killed at least 129 people and injured many others.

"These refugees are subject to the highest level security checks of any category of traveller to the US," Xinhua quoted State Department spokesman Mark Toner as saying on Monday. "We think we can do this safely and in a way that reflects American values."

Also on Monday, several US governors threatened to stop accepting Syrian refugees as the weekend attacks in Paris raised security worries over Syrian migrants.

Concerns highlighted after the attacks that terrorists might use the refugees as cover to sneak across borders.

One of the terrorists involved in Paris attacks was found to have a Syrian passport, and likely made it to the country in the cover of refugees, according to French police.

As millions of Syrians have fled to neighbouring Middle Eastern countries and Europe, US President Barack Obama had announced that his administration would admit at least 10,000 Syrian refugees in the coming year.