Divers recovered the body of a 45-year-old woman who drove a pickup truck into the water off the Mukilteo ferry dock early Thursday morning.

Chopper 7 video showed the white pickup in the water as a marine rescue boat and a county dive team responded.

Washington State Patrol investigators looked at ferry dock surveillance video that showed the woman drove around a gate arm and into the water at 2:30 a.m.

Four hours later, someone on a ferry spotted the white truck, partially submerged.

"They saw the truck was still partially floating, partially submerged, and it quickly sank under the water as first responders came out to the scene," said Cheol Kang of the Mukilteo Police Department.

A crew was working to float the truck and get it out of the water.

The medical examiner will determine the woman's cause of death.