Washington, Nov 17 (IANS): The US Secret Service charged with protecting President Barack Obama is investigating two bullets that hit the White House, one of them apparently cracking a window on the residential level, while Obama was travelling.

The bullet was stopped by a bullet-proof window and did not enter the White House, the Secret Service said Wednesday. Authorities also found another round in the exterior of the White House. The bullets were found Tuesday, the Secret Service said.

"A round was stopped by ballistic glass behind the historic exterior glass. One additional round has been found on the exterior of the White House. This damage has not been conclusively connected to Friday's incident, and an assessment of the exterior of the White House is ongoing," a Secret Service statement said.

There is no specific concern for Obama's safety, a Secret Service official told CNN. The bullets were found on the south side of the White House, he said.

Last Friday night at about 9 p.m., US Park Police and the Secret Service investigated after hearing shots fired about 700 to 800 metres from the White House, the Secret Service statement said.

Within five minutes, officers located a vehicle on Constitution Avenue. "Evidence in the vehicle led to US Park Police obtaining an arrest warrant for Oscar Ortega-Hernandez," described as a 21-year-old Hispanic male, 5 feet 11 inches tall and weighing 160 pounds.

A weapon registered to Ortega-Hernandez was found in the car, CNN said citing a law enforcement source familiar with the investigation.

Authorities are searching for Ortega-Hernandez, with the FBI, Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) and Metropolitan Police Department all taking part, officials said.