At least 300 fighters, primarily from Iraq's Badr and Nujabaa groups, crossed late on Sunday using a dirt road to avoid the official border crossing, two Iraqi security sources said, adding that they were there to defend a Shi'ite shrine.

The sources told Reuters that Hezbollah had not yet been asked to intervene, adding that the group was not ready to send forces to Syria at this stage following more than a year of hostilities against the Israeli military, including two months of heavy ground fighting in southern Lebanon.

"The Syrian Army does not need fighters," a Hezbollah spokesperson told Newsweek on Monday. "It can defend its land." The remarks came as the Syrian military attempted to organize