One or both of the two high school seniors slain on the eve of their graduation is believed to have known their shooters, Montgomery County Police said Friday.

Shadi Adi Najjar, 17, and Artem Ziberov, 18, were found dead in Najjar's Honda Civic on June 5, the night before they were set to graduate from Northwest High School in Germantown, Maryland.

Police Capt. Darren Francke said on Friday morning that investigators found graduation tickets at the scene.

They also found 30 shell casings, fired from multiple calibers of weapons, Francke said, describing the crime scene as "a very violent scene."

"We can't imagine what someone did to deserve this fate," he said.



One victim was shot 10 times; the other was shot four times, he said. The other rounds hit the car and points around the neighborhood, about five miles from where the victims had lived.

One of the victims was found clutching a $20 bill.

"Our experience, what we've learned from the crime scene, shows us that this is not a random event... We do believe that the suspects and the victims knew each other, and more importantly, we believe there are people out there who have not come forward yet and have not given us information that they know about this case."

Najjar and Ziberov, who were best friends, left Najjar's house about 7 p.m. the night of the shooting and never returned. Najjar's father said he sent his son several text messages asking if he was OK and where he was.

About five miles away from the victims' neighborhood, officers went to a quiet residential street in the 8200 block of Gallery Court in Montgomery Village after a neighbor reported hearing gunshots about 10:46 p.m.

A neighbor's surveillance camera picked up the sound of the barrage of gunfire. Faintly, a car can be heard driving away from the area. Police said on Friday morning that they've confirmed that the audio is authentic.

Police found the victims' bodies in Najjar's car, which was parked but still running.

Both victims were excellent students at Northwest High and had planned to attend college in the fall.

"I want everybody to know what happened exactly," said Najjar's father, Adi Najjar in the wake of the shooting. "Why he's shot? Maybe somebody saw something, will call the police. At least I'll have an answer, you know? Because I will never be able to sleep until I find the answer [to] who shot my boy and why they shot him."

Police are examining phone records, Frank said.

Anyone with information about this case is asked to call police at 240-773-5070. A reward of up to $10,000 is being offered for information that leads to an arrest. Frank said Najjar's father is working to increase the reward, and it's expected to reach $20,000 by the end of Friday.