Per Ardua

...ad Astra. From Space Daily :

Twenty-one people died in the explosion of a satellite launch rocket at Brazil's Alcantara space center near here, aeronautics officials confirmed Saturday.

The prototype launch vehicle was being prepared for Monday's launch into orbit of two Brazilian observation satellites when it exploded Friday, incinerating the bodies of the victims and destroying the satellites and launch pad.
...
The explosion was triggered when one of the rocket's four main thrust engines was unintentionally fired up. The 36-meter(118-foot) platform where the technicians were working disintegrated, officials said.
Defense Ministry sources said no injuries were reported. Everyone who had been working on the platform died in the sudden blast.

Almost all the dead were technicians from Sao Joao dos Campos, a city in the state of Sao Paulo which houses a number of aerospace companies.

The technicians were putting in place the final details relating to Monday's scheduled rocket launch.

Dulce et Decorum est, Pro Astra Mori. My sympathies to the families.