ABC News has learned authorities are increasingly concerned that a man sought in connection with a bizarre shooting incident on the Washington Mall last week may pose a threat to President Obama.

The Secret Service now suspects that a bullet fired in this incident may have hit the White House after a bullet round was found in a White House window, though the round had not yet been conclusively linked to the incident.  The round was stopped by ballistic glass behind the historic exterior glass, while an additional round has been found on the exterior of the White House.

Police believe the suspect, 21-year-old Oscar Ramiro Ortega of Idaho, is mentally ill. Ortega has an extensive record, ranging from domestic violence to drug charges. Sources say a police investigation has uncovered evidence suggesting Ortega has a fixation on the White House.

At 9:30 p.m. Friday, police received reports of shots fired in the bustling area of 16th street and Constitution Ave.

Authorities would later find a car in the area. The suspect had fled, but what police discovered inside the vehicle left them deeply concerned: an assault style rifle and empty shell casings.

Police linked the car to Ortega and have been hunting him ever since.

It’s unclear whether Ortega is capable of launching a sophisticated attack, but police are still fearful of what he might do next.

Authorities suspect Ortega has been in the area for weeks, coming back and forth to the Washington Mall.  Before the shooting, he was detained by local police at an abandoned house. U.S. Park police say Ortega may have spent time blending in with Occupy D.C. protesters.

President Obama, who is currently on a visit to Australia, was not present at the White House at the time of the incident, and in fact has been out of town for the past week. Secret Service officials are not taking any chances with the security of the President and the White House, though, and want Ortega off the street.