ST. LOUIS (AP) _ A Trans World Airline flight from St. Louis to Philadelphia was delayed about 20 minutes when a chemical believed to be ether leaked from bottles in a shopping bag, authorities said.

Phil Cushing, special agent for the Federal Aviation Administration, said the chemical seeped through two plastic bottles and the bag and onto some seats. He said the passenger who brought the bag onto the airplane in Los Angeles, where the flight originated, fled before he could be questioned.

Several seats were removed from the plane before it resumed its flight on Monday afternoon, Cushing said.

Ether is a colorless, flammable liquid used as an anesthetic and a solvent for resins and fats.