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. ||||| WASHINGTON (CNN) -- Police are still looking for a suspect in Friday night's shooting near the White House and Washington Monument and say they haven't found any bullets in buildings, cars or trees to indicate what the shooter might have been aiming at. No one was injured. 
 
 The U.S. Park Police have an arrest warrant out for Oscar Ramiro Ortega on a felony charge of carrying a dangerous weapon, and they would like Ortega to come forward. 
 
 "We want to hear from Mr. Ortega," said Park Police Sgt. David Schlosser." We want to hear his version as to what happened. This will help us fill in the blanks as to what actually occurred on Friday evening and we'd like to resolve this soon." 
 
 Witnesses -- including uniformed Secret Service officers -- heard shots fired Friday night. 
 
 Schlosser said he didn't know if Ortega had a history of anti-government activity or rhetoric and also did not know if he is a U.S. citizen. 
 
 Police found a crashed car near Theodore Roosevelt Bridge and say Ortega had been driving it. Schlosser said investigators found a semi-automatic weapon and shell casings inside the vehicle. That bridge is west of the White House and Washington Monument and is a major route into Virginia. 
 
 "The actions that Mr. Ortega participated on Friday evening -- that being the discharge of a firearm near the White House -- is an inherently dangerous activity, and because of that we do want to find Mr. Ortega as quickly as possible," said Schlosser. "At this point we're not certain what his intentions were." 
 
 On the same day the shooting incident happened, Ortega was stopped by police in Virginia around 11 a.m. for some sort of suspicious activity, said Lt. Joe Kantor with Arlington County Police. Kantor did not provide details on what behavior Ortega allegedly had been engaged in. 
 
 Ortega was not arrested in that stop, but Arlington County police took photos of him including one showing one of his tattoos spelling out the word "Israel" on his neck. U.S. Park Police later used those pictures in their releases asking the public for any information on the shooting incident. 
 
 Ortega is described as a Hispanic male, 5 feet 11 inches tall, weighing about 160 pounds. 
 
 According to the U.S. Park Police, the 21-year old Ortega has a history of criminal activity in three states that includes drug charges, underage possession of alcohol and assaults on law enforcement officers. Schlosser said the charges occurred in Idaho where Ortega was known to have lived, as well as in Texas and Utah. 
 
 Schlosser said law enforcement officials believe Ortega has been in the Washington area for several weeks.
– A suspect believed to have fired shots at the White House last week is still at large and police believe he may be a threat to President Obama. A semi-automatic weapon was found in a crashed car belonging to Oscar Ramiro Ortega, a 21-year-old Idaho man, CNN reports. Ortega has a fixation with the White House and a criminal record that includes convictions for domestic violence, drug offenses, and assaulting police officers, sources tell ABC. A bullet was found in a White House window after Friday's incident. It had been stopped by ballistic glass behind the historic exterior glass. Authorities believe Ortega has been in the DC area for weeks, repeatedly visiting the Washington Mall, and possibly blending in with Occupy protesters.