article_snippet.sent: Scroll down for video .
article_snippet.sent: Television reports showed aerial footage of firefighters working on the crash scene, which was strewn with the shattered remnants of the craft.
article_snippet.sent: Authorities said Authorities were investigating the cause of the crash.
article_snippet.sent: According to reports the aircraft was making a test flight after the exchange of a main rotor blade.
article_snippet.sent: Firefighters and policemen set up a cordon in the Sao Paulo off street where a helicopter crashed yesterday .
article_snippet.sent: Authorities said Authorities were investigating the cause of the crash .