RIO DE JANEIRO - A BURST of automatic messages sent by Air France Flight 447 offers few concrete clues into what made the plane crash into the Atlantic en route from Rio de Janeiro to Paris two weeks ago, an aviation expert said on Saturday.

The industry official, who has knowledge of the Air France investigation, told The Associated Press that a transcript of the messages posted on the website EuroCockpit is authentic but inconclusive.

GARNER (North Carolina) - AN explosion that killed three workers at a snack foods plant earlier this week was caused by a natural gas leak that ignited in a room housing vacuum pumps for sealing the snacks, authorities said on Saturday.

It will now be up to state and federal workplace investigators to determine how the leak happened and what caused it to ignite in Tuesday's blast at the ConAgra Foods Inc plant in Garner, said Earl Woodham, an agent with the US Bureau of Alcohol, Tobacco, Fireams and Explosives.

PERUGIA (Italy) - AMERICAN student Amanda Knox weathered a second day of tough questioning on Saturday over charges that she took part in the murder of her British housemate who refused to join in a group sex session in Italy.

Prominent public prosecutor Giuliano Mignini grilled the 21-year-old exchange student over her alleged role in an orgy that turned violent with the stabbing death of Meredith Kercher, 22, of Britain.