After a candle left burning in a motel room set fire to gas from a mobile methamphetamine lab, the operators drove themselves to a hospital in Slidell and are now in a Baton Rouge burn unit, the St. Tammany Parish Sheriff’s Office says.

Investigators plan to question Robert Fos Jr., 36, of Slidell, and Amanda Frierson, 29, of Saucier, Miss., later this week, said Capt. George Bonnett, a sheriff’s office spokesman.

He said their hands, legs, faces and chests were burned.

The lab allegedly was set up in a hotel room in Picayune, Miss., but the two drove themselves to a hospital in Slidell and were taken from there to a burn center, authorities said.

Baton Rouge General Hospital has south Louisiana’s only burn unit.

Bonnett said Fos’ father, whose name he did not give, retrieved the Jeep sport utility vehicle from the Slidell hospital after being notified that his son was in the hospital. Police, who had been called by hospital personnel, found him dumping items into a trash bin behind the hospital.

“He just knew something smelled bad and wanted to clean the car out,” Bonnett said.

A crew in hazmat suits and using oxygen tanks went through the car and the trash bin, setting aside items including drain cleaner, coffee filters, plastic tubing and nasal decongestant tablets onto a blue tarp.

Over-the-counter cold and sinus tablets containing ephedrine or pseudoephedrine are among ingredients of crystal meth.

Because Fos’ father had been exposed to the chemicals, the hazardous materials crew had him strip down and wash off while they held up a black tarp around him.