A rescue effort was launched Tuesday in Rochester for a 16-year-old boy missing in the Chehalis River.
Thurston County dispatchers said dive and rescue teams were scouring the area in the 12000 block of Independence Road SW.
A group of teens were enjoying the day with a swim when one of them got into trouble, said Lt. Lanette Dyer, West Thurston Regional Fire.
"Unfortunately he went under the water and he has not returned to the surface," she said.
About 30 people were helping search.
Dyer said the river looks inviting but is dangerous.
"People really need really realize that this is the time of year they need to think about their safety and the safety of people that are around them," said Dyer.
Divers planned to to search until dark.