As the Wootton High School community mourned the deaths of two teenagers killed in a late-night car crash, the 18-year-old driver remained in a hospital in critical condition, Montgomery County police said Saturday.

Police said they are continuing to investigate the fatal collision, just before midnight Thursday, but believe alcohol and speed were contributing factors.

The two teenagers killed — Alexander Murk, 18, of Potomac, and Calvin Jia-Xing Li, 18, of Rockville — graduated last month with Wootton’s Class of 2015. The driver, , Samuel Joseph Ellis, also a May graduate, was Wootton’s star quarterback.

The three teens and another friend, who received minor injuries, had been at a party where underage drinking occurred before they got into the car, police said. Ellis lost control while driving along Dufief Mill Road in North Potomac. The teenagers who died were not restrained with seatbelts, police said.

“We’re looking to conduct a thorough investigation as quickly as possible,” Montgomery Police Capt. Tom Didone said. No charges have been filed in connection with the crash, he said. About eight young people outside the party were cited for underage alcohol possession, he said.

Near the site of the crash, shaken students and parents braved the rain Saturday and dropped by a makeshift memorial, where bouquets of flowers were laid out, along with candles, American flags, a football and a sign that read #woottonstrong.

“They were the ones to put a smile on people’s faces,” said one teenager, who declined to give his name but described himself as a close friend of those involved.

“They were a big part of the Wootton family,” said another.

Others spoke of devastation across the community. A vigil was held at the school Friday night.

“People are just literally in shock,” said Rachel Boxman, mother of a senior at Wootton. “I know there are people who woke up today and said, ‘I just can’t believe this is real.’ ”

In a Facebook message to The Washington Post, a football teammate, Jason Lazar, described Ellis as an “awesome player” who made things happen and brought the team to victory many times.

Li, he said, was a wide receiver at Wootton who “played with extreme passion for the game and always put in his best effort, no matter the circumstance.”

He said Murk was headed to Penn State. “A great kid,” Lazar said. “He always knew how to make you laugh or smile. He made countless jokes and would brighten any room. He also had a fashion style rivaled by no one.”

Boxman said the deaths have been “excruciating” for a close community. People are praying for all the affected families, she said. “They have such a hard road ahead of them,” she said. “I have no doubt this community will pull together.”