During a religious celebration on "All Saints Day" a grotto in Santa Maria had collapsed leaving more than 10 people dead and 6 others injured, more than 50 believers attended the celebration, children were also present among worshippers.

The Casa da Pedra grotto is outside the city of Santa Maria and it has always been open to religious gatherings for locals for years as per RT News.

The roof of the grotto had collapsed together with victims trapped inside; the incident took place during a traditional mass on "All Saints Day". Though the mass was held outside the cave many people went inside to light candles and pray. The Mayor of the city Helen Ruth de Freitas stated that she never imagined such a tragedy of this magnitude.

According to Reuters, it is still not clear what had caused the collapse, some media reports stated that the bodies of the dead have all been recovered. Post the accident the site has been closed and is still pending a full investigation.

There have been several instances that occurred in many places around the world, but this incident was unexpected as the religious site was always open to pilgrims for many years and there was no chance of such an accident.

"All Saints Day" is celebrated widely in Brazil and its neighboring Country Argentina, it is a Catholic celebration which is always held on November 1st every year followed by "All Souls Day" which is on November 2nd.

The crowd was not that much at the grotto but cave was surely a small place to accommodate 50 plus people, the victims did not have time to realize that the roof of the cave was dropping down. It appears that all this had happened in a fraction of a second leaving them no time to run out for safety.