Story highlights "We've lost a lot of family members, church family," a man whose father died tells CNN affiliate WPBF

Eight people are dead, 10 are injured after a church van crash in Florida early Monday

Investigators don't know why the van ran a stop sign and plunged into a shallow canal

(CNN) A dark intersection. A church van full of parishioners. And tragedy.

That's about all police in Glades County, Florida, had to work with early Monday, hours after a van with 18 people inside ran a stop sign, crossed a four-lane highway and plunged into a shallow water-filled ditch. Eight people died. Ten others, including a 4-year-old child, were injured, according to police.

Investigators don't know why it happened, Florida Highway Patrol spokesman Lt. Greg Bueno told CNN affiliate WPBF . The driver died, and police haven't been able to interview passengers yet.

"Our hearts go out to the families of the victims," Bueno said. "It breaks your heart to see something like this happen."

Some relatives of the crash victims, all of whom were from the Independent Haitian Assembly of God in Fort Pierce, gathered at the rural intersection Monday morning. Others went to the church.

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