(CNN) -- Thirteen people traveling in a minibus bringing senior churchgoers back from a retreat were killed Wednesday in a two-vehicle crash in the Texas Hill Country, officials said.
Two people were injured, including the driver of a large white pickup that collided with the bus, said Sgt. Conrad Hein with the Texas Department of Public Safety.
"It was a really gruesome scene," motorist Rick Ballesteros of Uvalde, who drove up to the crash site, told CNN affiliate KABB.
Sgt. Orlando Moreno of the public safety department told reporters the 12 people, including the bus driver, died at the scene. The 13th victim died at a San Antonio hospital, about 75 miles away.
The 14th person on the bus is in serious but stable condition, according to the church.
The bus was taking congregants of the First Baptist Church in New Braunfels back from a retreat, the church said on its Facebook page.
Moreno said the bus was traveling south when the northbound pickup truck veered into its lane and hit the bus. The accident happened on a curve where the speed limit is 65, but the cause of the accident is still under investigation, authorities said.
The bus was traveling from Alto Frio Baptist Encampment in Leakey when the accident occurred near Garner State Park, about 7 miles away, on a two-lane section of Highway 83.
The church canceled events, but members gathered inside Wednesday night.
Senior Pastor Brad McLean said they were doing what church families do during crises.
"They're coming together, they're crying together, they're praying together and ... there's anxiousness as to who was on the bus and what their condition is." McLean said authorities had not yet given him details about the accident.
The church's Facebook post asked for prayers.
"We are ministering to family members to help them deal with this tragedy. Counselors will be on hand at the church tomorrow," the church wrote. "If you're a Christian, you can pray for those who lost their loved ones and for the church family."
Gov. Greg Abbott sent his condolences to the victims' families.
"We are saddened by the loss of life and our hearts go out to all those affected," Abbott said.