Around 6,000 sightseers came to see the wreckage , their presence causing congestion in the narrow lanes and necessitating the area being cordoned off .
The investigators could carry out their work and also to prevent contamination of the evidence .
Around 6,000 sightseers came to see the wreckage , their presence causing congestion in the narrow lanes and necessitating the area being cordoned off so that the investigators could carry out their work and also to prevent contamination of the evidence .