Miza Saleh stands with her daughter, Nora Alshareef, 20, on June 6 while talking about the shooting deaths of Northwest High School students Artem Ziberov, 18, and Shadi Najjar, 17. (Matt McClain/The Washington Post)

At least two gunmen appear to have targeted a pair of Maryland high school students killed on the eve of their graduation this month — firing at least 30 rounds at the students’ car that was stopped along a quiet suburban cul-de-sac just before 11 p.m., Montgomery County police officials said Friday.

The victims — Artem Ziberov, 18, and Shadi Najjar, 17 — suffered a total of 14 gunshot wounds. One had 10 wounds; the other four.

“Based on our experience, based on what we know about the victims, we believe they were targeted,” said Capt. Darren Francke, commander of the major crimes unit at the Montgomery Police department just north of Washington. “We believe there was more than one shooter.”

The June 5 slayings of Najjar and Ziberov were stunning in their brutality and timing. Both students had been on the honor roll at Northwest High School in Germantown and were set to walk across the stage at their graduations the next day. Friends have widely described them as smart and pleasant — with few, if any, known enemies.

For reasons still unclear, Najjar drove to a Montgomery Village neighborhood, miles from his home, and parked along the edge of Gallery Court, a short street of 18 homes. His friend Ziberov was in the passenger seat. One or both teens probably knew members of another party that met them there, police officials said.

The scene in Montgomery County, Md., where the two teens were shot in what police suspect was a targeted killing. (Dan Morse/The Washington Post)

The attackers unleashed a barrage of gunfire, prompting at least one 911 call. When officers arrived, the other party was long gone, the young men were dead and the Honda’s motor was still running.

Police officials have since released limited information — in part because they don’t want to damage their investigation and in part because they have reached a limited number of conclusions.

“It’s a challenging case,” Francke said, “because there is a lot of forensic evidence and data we have pulled. We have to sort through that carefully. But we don’t have any eyewitnesses that have come forward yet.”

Detectives are piecing together a timeline of what the teenagers did in the hours leading to the killing, and what their plans may have been for the balance of the night.

“We have a good deal of information, but I can’t comment on it,” Francke said at a news conference Friday.

Asked if drugs or drug purchases may have played a role in the slayings, Francke would say only that detectives are looking into many scenarios. “They would have no normal course of business in that neighborhood, on that street,” he said of the two teens.

His detectives are still trying to learn why, then, they went there.

“We’re looking at different ­social-media platforms to try to determine what the victims were doing, who they were talking to, and what they may have been into,” Francke said.

Police found 30 ammunition casings — from bullets of at least two different calibers — at the crime scene. Francke said neither he nor other detectives could recall a recent shooting scene in Montgomery County with that many casings found.

He again appealed to the public for help. “Someone out there has information that we need,” he said.

“There are individuals with critical information in this case,” he added. “To those that are holding it, do the right thing, the safest thing, and speak with the police.”

Francke said there has been no indication this was a hate crime or motivated by race or nationalities.

Asked if the targeting of the victims could have been the result of an impromptu meeting — spurred, for example, by an argument at a red light — Francke said the evidence does not suggest that.

“Based on the crime scene, that doesn’t seem likely,” he said.

Investigators also are talking to the victim’s family members, who are going over events of the last six months to try to come up with information or interactions that might be helpful. “Both families have been very cooperative,” Francke said.

Police declined to say which victim had 10 gunshot wounds. But Francke stressed that the total doesn’t necessarily establish anything about an intended target and may reflect that there were different shooters firing guns.

There are indications that one of the victims was targeted, but detectives can’t draw a firm conclusion yet, because they are still gathering information. Detectives don’t know if more than one car was used by the shooters, according to Francke.

The commander doesn’t believe — based on what his investigators have learned about the victims — that they were into any behavior that would have drawn in assailants from outside the region or the state. “I think the shooters are local” to the Washington area, he said. “We don’t have any reasons to believe they are somewhere else. Whatever issues the victims had with them were local to area.”

It is unclear if detectives have found surveillance video that could help them. They have received, from a resident of the cul-de-sac, an audio recording captured by his surveillance system of the sound of the shots being fired. Detectives have studied this — listening to the shots and listening for any background noises.

Crime-scene investigators recently dusted the back door of Najjar’s residence for fingerprints, trying to determine if someone who might be connected to the homicides had tried to break into the home. That line of investigation has not yielded information. “I don’t think it amounted to anything,” Francke said.

A core of major crimes detectives is working the case — part of as many as 60 investigators and crime scene technicians playing a part in interviewing people and analyzing evidence, according to police officials.

Anyone with information is asked to call 240-773-TIPS (8477) or 240-773-5070.