Senior Obama Administration officials said the 50-member Marine unit was being flown from their base in Europe. This is in addition to two US warships USS Laboon and USS McFaul which are now being moved to the coast of Libya.
The warships are equipped with Tomahawk missiles that could be used if the Obama Administration orders a strike against those responsible for the attack on US mission.
The crews of each warship equal approximately 300 people. The decision comes after US envoy to Libya and three other Americans were killed in the attack on the US consulate in Benghazi by an armed mob on Wednesday.
The move came hours after President Barack Obama said he has directed his administration to provide all necessary resources to support the security of US personnel in Libya, and to increase security at diplomatic posts around the globe.
Pentagon spokesman George Little declined to comment on specific ship movements but said precautionary steps are being taken by the US military.
"The Fleet's Anti-terrorism Security Teams (FAST) that we deploy when requested are responsible for the protection of Embassy personnel and property, and they also play a role in the evacuation of personnel, as required," the senior administration official said on condition of anonymity.
"Whether or not US military personnel will be involved in future operations to track down the perpetrators of this attack, I'm simply not going to speculate on what may or may not be in the works in the future," the official said.
According to the official, the Department of Defence is working closely with the White House and State Department to provide all necessary resources to support the security of US personnel in Libya.
The FAST teams were formed in 1987 to provide a quick response to security threats after a series of terror attacks on American interests in the 1970s and 1980s.
"This support includes a Marine Corps fleet anti-terrorism
security team based out of Europe. The mission of this team is to secure the diplomatic facility in Tripoli, our Embassy, and protect US citizens as needed," the official said.
The Defence Department is also providing support to evacuate American personnel and casualties out of Libya.
"Those individuals and the remains of our fallen colleagues will arrive, if they haven't already done so, at Ramstein Landstuhl in Germany," the official said.
According to WAVY-TV, the USS Laboon, along with other Norfolk-based destroyers, had been recently equipped with the Ballistic Missile Defence System.
Those destroyers are the cornerstone of what is called the President's "Phased Adaptive Approach" to protect European allies from growing missile threats, said the Norfolk-based local television channel.
Meanwhile, Obama telephoned his Afghan counterpart Hamid Karzai to discuss and ensure that the violent incidents in Libya and Egypt do not have any negative impact on the safety and security of American soldiers deployed in Afghanistan.
"Karzai expressed condolences for the tragic loss of American life and the Presidents discussed the importance of working together to help ensure that the circumstances that led to the violence in Libya and Egypt do not pose a threat to US forces or Afghans," the White House said.
The White House said Obama called Karzai as part of their regular consultations as transition continues in Afghanistan.
The two Presidents took the opportunity to discuss the tragic events that took place in Benghazi, including the death of US Embassy personnel.
"Obama also reaffirmed his commitment to transferring detainees to Afghan authority in a manner that respects Afghan sovereignty and protects US and Afghan forces. The two Presidents agreed to speak again soon on additional issues of mutual interest,"" the White House said.
