Egyptian Vice President Omar Suleiman was recently the target of an assassination attempt, in which two of his bodyguards were killed.
According to Fox News, a senior Obama administration official confirmed that the attack happened soon after Suleiman was appointed on January 29.
The official described it as an organised attack on Suleiman's motorcade.
However, White House Press Secretary Robert Gibbs declined to address the assassination reports saying, "I'm not going to get into that question."
President Hosni Mubarak, who is facing intense pressure to resign, had named Suleiman as vice president in an effort to quell the anti-government protests in the country.
Suleiman may take over as interim leader of Egypt in some of the proposals reportedly being considered for an expedited political transition.
Mubarak had earlier this week announced that he would end his nearly 30-year rule, but only after elections in September.