Fox News says the United States has deployed some Marines and two amphibious ships to help with the evacuations in Libya.
The news comes one day after the U.S. moved naval and air forces closer to Libya and said all options were open, including patrols of the North African nation's skies to protect its citizens from their ruler, Muammar Qaddafi.
The Obama administration is demanding that Qaddafi relinquish power immediately.
Secretary of State Hillary Rodham Clinton warned that Libya is at risk of collapsing into a "protracted civil war" amid increasingly violent clashes between the two sides.
On Tuesday, U.S. Ambassador to the United Nations Susan Rice cast doubt on Qaddafi's sanity and ability to lead and said the international community will continue pressuring Qaddafi with embargos and sanctions until he steps down.
"Any time you have somebody who laughs with American and international journalists while slaughtering his own people, I think they're not only delusional, one has to question their grip on reality," Rice said on NBC's "Today Show," referring to an interview Qaddafi gave Monday to ABC and the BBC.
"We have to assume that we're dealing with somebody who is no longer--if ever was--fit to lead his nation and whose behavior is unpredictable and irrational," Rice added.
The turmoil in Libya drove stocks down again on Tuesday as oil prices hovered near $100 a barrel.
More than 140,000 people have fled Libya to Egypt and Tunisia in a growing exodus from the chaos engulfing the country, refugee officials said.
U.N. refugee agency spokeswoman Melissa Fleming said Tuesday "the situation is reaching crisis point" at the Libya-Tunisia border where authorities say up to 75,000 people have fled Libya since Feb. 20. Egyptian authorities say 69,000 people have crossed over from Libya since Feb. 19.
International pressure to end the crackdown has escalated dramatically in the past few days.