Multiple people have been rescued after a seaplane carrying 11 people made an emergency landing Thursday off the coast of Washington, prompting a multi-agency search and rescue operation.

All 11 people, a pilot and 10 passengers, aboard the Kenmore Air seaplane have been accounted for after the plane made an emergency landing and caught fire near Sucia Island in the San Juan Islands, the US Coast Guard told CNN.

Four people were transported to hospitals with serious injuries, CNN affiliate KING reported citing a Kenmore Air spokesperson. One of the four injured passengers was transported in critical condition, San Juan County Sheriff Eric Peter said, according to KING.

The victims’ injuries range from “head injuries to broken bones and lacerations,” Peter said.

What prompted the plane to make an emergency landing is unknown.