Christine Lewis, 51, of Visalia was discovered in a section of the river along the California-Arizona border, Mohave County Sheriff's Office spokeswoman Anita Mortensen said.

Lewis was among more than a dozen people ejected from the boats in the crash Saturday night.

A search continued for two other women and one man.

A recreational boat carrying 10 people and another vessel with six people on board collided head-on Saturday night along the well-traveled stretch of the river, the office said.

Both boats sank, and passing boaters pulled crash victims from the water. Nine people were injured, with two in critical condition, authorities said.

The cause of the crash is being investigated.

None of the boaters were wearing life jackets, which aren't required but are recommended by authorities, Mohave County Sheriff Doug Shuster said.

The crash occurred between two popular marinas and near Moabi Regional Park, as people enjoyed the Labor Day weekend.

Helicopters have been deployed as part of the search, and authorities have scoured the shoreline. Divers have been sent into the river, which can run as deep as 30 feet (9 meters).

"These efforts will continue until all of those who are missing and unaccounted for have been located," Shuster told reporters.

Authorities closed off a stretch of the river where the search was taking place.