Two helicopters with passengers who were filming a documentary have crashed in a remote area of northwest Argentina, leaving at least 10 people dead.

Secretary of Security Cesar Angulo told television station TN that the helicopters crashed Monday afternoon while flying near Villa Castelli in La Rioja province, about 720 miles (1,170 kilometers) northwest from Buenos Aires.

Angulo said there was an explosion and authorities believe the helicopters might have collided but that an investigation was ongoing. Angulo did not release names of the deceased or any more details.