Charles Hu had a lot to say last November at Highrock Church in Arlington when he rose to speak at a meeting of the young adult ministry. The message was quintessential Charles.

“In a loving way, in a Charles way, he kind of said, ‘You all have to get off your lazy butts and go serve, and go volunteer, and live out our vision statement,’ ’’ said Ezer Lee, young adult ministry director at Highrock. “He wanted us to step up.’’

That memory was among many Lee reflected on Wednesday, a day after Hu, 26, was killed after a wheel broke off a pickup truck driving south on Route 128, crossed a median, and hurtled into his sedan. Hu, who lived near the crash site in Lexington and was driving in the opposite direction, was declared dead at the scene.

Church leaders said they were among the first to learn of Hu’s death from police attempting to notify his family. Hu’s parents were out of the country when the crashed happened about 1:15 p.m. Tuesday, according to several church leaders and a relative.

“I must have read that police report 10 times thinking, ‘How is this possible?’ ’’ said David Swaim, lead pastor at Highrock Arlington. “It’s unbelievable.’’

The wheel also collided with a Toyota Highlander traveling north, driven by a 50-year-old Braintree man who was not injured.

The Dodge Ram pickup truck was driven by a 19-year-old Amesbury woman, who has not been named by authorities. She was not hurt.

Investigators are focused on determining why the left rear tire of the truck separated from the axle, said State Police spokesman David Procopio.

The inquiry, which is expected to take several weeks, will include an examination of the truck, its service records, and evidence collected at the scene, Procopio said.

Investigators also plan to review a database to determine whether any recalls were issued for the vehicle’s axle or wheelbase.

Their findings will dictate whether criminal charges are filed, Procopio said.

On Wednesday, the mourning for Hu stretched from his church in Arlington to Taiwan, where his parents learned of the crash.

“We are very, very shocked and very, very sad,’’ Hu’s uncle, Jeff Chen, said by phone from California. “He is a very kind person. He cared for his family.’’

Hu was raised in Lexington and graduated from Brandeis University in 2011. Seven months ago, he went to work for athenahealth Inc., a health care technology company in Watertown, the company said.

Standing more than 6 feet tall, Hu was hard to miss. At Highrock, many of his contributions were musical.

“Music was a way for him to be part of the community,’’ said Eugene Kim, the church’s executive pastor.

Hu sang bass and performed with the church choir for the Christmas Benefit Concert, an annual weekend of shows that raise money to pay for a social worker at the Arlington Youth Counseling Center. He also played bass and acoustic guitar in a band that performs at Sunday services.

Hu was scheduled to perform with the group this Sunday, said John Mury, a pastor at Highrock.

“He’s the kind of guy that everybody wants to be with,’’ Mury said. “A lot of people are in shock.’’

Hu also had a reputation for being curious. He was never afraid to pose questions about his faith, several church leaders said.

“He really listened well and asked questions,’’ Swaim said. “Both in his relationship with God and in his relationships with people, he’s so inquisitive and really wanted to learn and think and get things right.’’

Church leaders said they last saw Hu at services Sunday. After church, some people stayed to watch the New England Patriots game, but Hu left to take his girlfriend on a date, according to Lee. Before they parted ways, he said he chatted with Hu about plans to establish a winter basketball league, and they promised to see each other next week.

Mury described what happened to Hu as “winning the negative lottery.’’

“I think of him as a bright young man who had everything,’’ he said. “Now, it’s taken away.’’

Laura Crimaldi can be reached at laura.crimaldi@globe.com Follow her on Twitter @lauracrimaldi.