SABINE PASS, Texas — A helicopter with five people aboard crashed into the Gulf of Mexico on the way to an oil rig early Thursday, and rescue crews have picked up one survivor and continue to search for the others.

Coast Guard Petty Officer Renee Aiello said the Coast Guard was alerted at 9:47 a.m. by a call from the helicopter leasing company Rotorcraft Leasing Co. LLC of Broussard, La., which reported that the pilot had not checked in as scheduled.

A rescue helicopter crew found one adult male and debris in the water about two miles off the Texas coast. The man is alive but his condition is unknown, Aiello said.

"We know there was an event that took place; we're still in the process of searching," said Gerald Golden, director of operations for Rotorcraft. "Once we learn anything, we'll be in a position to give more details."

The helicopter was headed toward an unmanned oil platform in the Gulf of Mexico about 18 miles offshore, Aiello said.

The air temperature was about 36 degrees, with water temperatures at 62 degrees around the time of the crash, said Donovan Landreneau, a meteorologist with the National Weather Service in Lake Charles, La. Wind was blowing from the west at 23 knots, and there was a small craft advisory in effect.

A spokesman for the National Transportation Safety Board in Washington said investigators would work with the Federal Aviation Administration to determine the cause of the crash.

Sabine Pass is about 90 miles east of Houston.