Four boys and one girl drowned in a Missouri river during a church excursion, authorities said Monday. A sixth child was rescued and is in hospital.

Officials said one of the children became trapped in the powerful undertow of the Meramec River near St. Louis, prompting the five youngsters to jump in to offer help on Sunday evening.  

The children, whose ages ranged from nine to 15, had been celebrating a volunteer appreciation day at Castlewood State Park with the St. Louis Dream Center, an interdenominational church. 
 
"Let me say this is one of the most horrendous things a church family, any family, would have to go through," said church pastor Jeff Allensworth, who asked the public to pray for the community.

Parents said the children knew how to swim, said Tracy Panus, a spokeswoman for St. Louis County police.

Rescue crews, who received a call at 6:30 p.m. on Sunday, arrived to find two of the children had been pulled from the water. One child died and the other remains in hospital.

Crews worked through the night and pulled the last body from the river around 6 a.m. Monday. Authorities said the rescue effort was slowed by conflicting reports regarding how many children were at the event and how many were missing.

The bodies of the children were found in water about 2.5 to 3.5 metres deep, close to 200 metres downstream from where they are believed to have entered the river. 

"It was just depressing," Panus said. "It was horrible. You have a church group out there for a good reason, a good cause. No one is out there drinking or getting stoned, and a tragedy can
happen just like that. It's kids and it's tragic."

With files from Associated Press