WATCH VIDEOS: Moving speeches, moments at funeral of Hayward Police Sgt. Scott Lunger
It's called a U.S. Honor Flag and it flew for 15 hours in memory of fallen Sgt. Scott Lunger.
It's flown at several landmarks across the U.S., including Ground Zero in New York City, and travels across the country to honor American heroes.
Sgt. Lunger was shot during a traffic stop 12 days ago.
The 15 hours the flag flew matches the number of years Lunger served the citizens of Hayward.
PHOTOS: Procession, memorial for fallen Hayward Sgt. Scott Lunger
Mark Estrada of Oakland suffered a gunshot wound to the leg during the shooting and has been charged with murder with three special circumstance clauses.
Police say the 21-year-old admitted to a doctor that he was shot while sitting in the driver's seat of his truck in Hayward, but refused to say who shot him.
VIDEO: Friends, family give touching tributes to slain Hayward sergeant
Those who would like to make donations to help with the college expenses of Sgt. Lunger's two daughters Saralyn and Ashton can send donations here:
HPOA (Hayward Police Officers Association)
C/O Family of Sgt. Scott Lunger
300 West Winton Avenue
Hayward, CA 94544
Click here for full coverage on the Hayward police shooting.
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