Bijan Ghaisar's sister says 'this isn't over' two years after killing by U.S. Park Police

Two years after U.S. Park Police shot and killed an unarmed man after a minor traffic accident, friends, family and lawmakers gathered on the anniversary of the shooting with renewed calls for accountability and answers.

The gathering Sunday at the Lincoln Memorial came just days after the Department of Justice announced it will not bring federal charges against the officers who shot Bijan Ghaisar in Fairfax County.

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"My parents were very patriotic growing up, my dad in particular," said Negeen Ghaisar, Ghaisar's sister. "We used to come to the Lincoln Memorial all the time, typically at night. That was kind of our thing."

The memorial means something much different now. It's where the family has gathered three years in a row. Their plea hasn't changed. They want to know why the officers killed Ghaisar.

The scene at a vigil Sunday for Bijan Ghaisar, two years after he was shot and killed by U.S. Park Police.

Ghaisar's family was joined by several members of Congress who say, despite the DOJ conclusion, this is not over.

"The full FBI investigation must be made public," said Rep. Don Beyer, D-VA.

Beyer along with Rep. Eleanor Holmes Norton (D-DC), and Rep. Jennifer Wexton (D-VA) wrote a letter urging U.S. Park Police to open an internal investigation into the killing of Ghaisar.

They want a response in writing no later than Dec. 5 on whether Park Police will conduct an internal investigation, its scope, the duty status of the officers, and any investigation's expected completion date.

A Park Police spokesman tells FOX 5 the agency has not started any internal investigation because the DOJ probe was still underway. He said both officers involved in the shooting remain on paid desk duty.

Sen. Mark Warner (D-VA) and Sen. Chuck Grassley (R-IA) are calling for a DOJ briefing about the decision not to pursue charges.

RELATED: Department of Justice won’t pursue criminal civil rights charges against Park Police in Bijan Ghaisar case

"You still haven't given us any answers!" said Negeen during the rally. "This is not over!"

What led up to the shooting two years ago started when a driver hit Ghaisar's car on the George Washington Parkway near Alexandria and Ghaisar drove off. Park Police pursued him and officers ending up shooting at him 10 times. The officers have said they were in fear for their lives, but Ghaisar had no weapon and we don't know what it was that prompted them to open fire.

Ghaisar's family filed a civil suit against the officers, Alejandro Amaya and Lucas Vinyard, in August 2018.

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"For me, there is a big hole in my heart for the rest of my days," said Ghaisar's father, James Ghaisar.

"I think that the saddest and most amazing thing is watching how resilient, how amazing, how strong (my parents) are," said Negeen. "That despite everything that has happened they still stand and they still fight."