Washington: The US is deploying warships and surveillance drones in its hunt for those who killed four US diplomatic staffers in Libya, CNN reported Thursday.
US ambassador to Libya Christopher Stevens died in Libya`s eastern city of Benghazi Tuesday, along with another diplomat and two State Department security officers, when a mob stormed the US Consulate and set it ablaze.
The consulate faced protests after the online release of a film that allegedly insulted Muslims and Prophet Mohammed.
US sources quoted by CNN said the four-hour assault in Benghazi had been planned beforehand, with the attackers using the protest as a diversion.
A senior US official said that American surveillance drones are expected to join the search for jihadists who may be tied to the attack.
The drones are expected to gather intelligence that will be turned over to Libyan officials for strikes, the official said.
Two US destroyers -- USS Laboon and USS McFaul -- equipped with satellite-guided Tomahawk cruise missiles are also en route the Libyan coast, US officials told CNN.
President Barack Obama said: "We will not waver in our commitment to see that justice is done for this terrible act. And make no mistake, justice will be done."
Obama called Libya`s newly elected president Mohamed Magariaf, and thanked him for his condolences on the deaths of the Americans.
"The two presidents agreed to work closely over the course of this investigation," the White House said in a statement.