Information on the nationalities of those aboard was not immediately
available.

Argentine and Uruguayan rescue teams rushed to the crash site on a
large farm in an area dotted with marshes and hills, about 280 miles
(450 kilometers) north of the capital, Buenos Aires.

There was no clear sign of what may have caused the crash, said Brig.
Juan Manuel Vazquez, secretary-general of the Argentine air force.

A witness, Gonzalo Vastos, told Uruguay's Cablevision Noticias that he
saw ``a ball of fire fall behind a hill'' and then a ``huge
explosion.''

Ingrid Bidegain de Bastos, who lives on a nearby farm, said she went
out to watch ``a strong electric storm and flooding'' when she suddenly
saw a ``red ball that fell and exploded on hitting the ground.''

Seventy passengers, including three infants, and five crew members were
aboard the flight from the northern Argentine city of Posadas to Buenos
Aires, said Santiago Garcia, commercial manager of Austral, a
subsidiary of Aerolineas Argentinas.

The plane had last made contact with Buenos Aires municipal airport
about 40 minutes before the crash and reported it was changing its
course to avoid heavy rain and hail near the capital, air force
official Jorge Carnevalini said.

In Uruguay, an air force official told The Associated Press on
condition of anonymity that the plane entered an area of heavy
turbulence. Other planes in the area also had reported severe
conditions at the time, he said.

A meteorological expert in Rio Negro said there was an unusually strong
storm which whipped up ``severe wind currents'' at the time of the
crash.

Meanwhile, early Saturday morning, more than 100 relatives of the
passengers and crew gathered at Buenos Aires metropolitan airport,
hugging each other in grief. A priest walked among them, trying to
comfort them, witnesses said.

Austral suffered a crash in June 1988 when a DC-9 smashed into a
fog-shrouded hillside outside Posadas, killing all 22 people aboard.
