A church bus carrying senior adults returning from a retreat in southwestern Texas on Wednesday collided head-on with a pickup truck, killing 13 people and injuring two others.

At about 12:20 p.m., the small passenger bus, carrying 14 people, was traveling south on the two-lane highway when a white Dodge pickup truck veered into its lane, striking the bus and killing 12 passengers on the scene, including the bus driver.

One woman died later in the hospital, while the one surviving passenger, a woman, remained in “serious but stable” condition. The driver of the truck received medical treatment for his injuries and remained in stable condition Wednesday night.

All of the people who died were members of the choir at First Baptist Church in New Braunfels, Tex., and had just attended a three-day retreat at Alto Frio Baptist Encampment in Leakey, Tex. The crash occurred about 120 miles from the church, where the bus was headed.

Marcia Dean, a church member and former employee, told The Washington Post the group of senior church members on the bus “had a fabulous time” at the retreat.

“They sang and laughed and praised the Lord,” Dean said.

The cause of the crash is still unknown, said Texas Department of Public Safety Lt. Johnny Hernandez, and authorities continued to reconstruct the incident late Wednesday night. The National Transportation Safety Board has sent investigators to the scene, NTSB announced on Twitter.

Those killed were “parents and grandparents” and some of the most active members of the church’s tightknit congregation of fewer than 500 people. The bus driver was retired teacher Murray Barrett, the San Antonio Express-News reported.

Amity Dohoney, 21, told the Express-News that the bus driver had taught her seventh- and eighth-grade math and that they remained close through the church.

“He was always such an upbeat person,” Dohoney said. “He loved people. He’d do anything to help them.”

The New Braunfels church was packed late into the night Wednesday, as several of the families of those who were on the bus gathered to wait for authorities to confirm the names of the dead.

They received the news shortly before 9 p.m., Dean said. Local restaurants have provided food to the church to feed the families, and pastors from other churches have reached out in support. Counselors will be on hand at the church on Thursday.

At about 7:15 p.m., three dozen people from a Lutheran church across the street held hands and silently walked over to join the families mourning, the San Antonio Express-News reported.

“Our community has rallied around us,” Dean said. “We’ve been talking, we’ve been hugging, we’ve been crying and telling stories.”

Texas Gov. Greg Abbott and his wife, Cecilia, offered their condolences in the hours after the crash.

“We are saddened by the loss of life and our hearts go out to all those affected,” their statement said. “We thank the first responders working on the scene in the wake of this unimaginable tragedy, and ask that all Texans join us in offering their thoughts and prayers.”

Many of the families and church members felt a sense of peace that those who died spent their final days praying and having a “blast.”

“They’ve gone home,” Dean said.

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