The Pentagon has dispatched a team of 50 elite U.S. troops to help bolster the security of American personnel in Libya, according to defense officials, The Christian Science Monitor reports.

The Department of Defense stands “ready to respond” with military measures as directed by the president, said a senior administration official who spoke on condition of anonymity during a background briefing with reporters Wednesday afternoon.

The U.S. Marine Corps unit, known as the Fleet Antiterrorism Security Team (FAST), is specially trained to protect – and when necessary, extract – U.S. citizens, as they did when they were sent to bring home U.S. citizens in Liberia in 2003 and in Haiti in 2004.

In the wake of the death of U.S. Ambassador Christopher Stevens, who was killed when armed militants overran the consulate in Libya’s second largest city, President Obama vowed to step up security at U.S. diplomatic posts around the world.