Carnival revellers in Rio danced until dawn yesterday, protected by unprecedented numbers of troops and police sent in after drug gangs threatened to ruin the parade.

An estimated 70,000 people cheered as the carnival queen, wearing little more than body glitter, inaugurated the samba schools competition in the sambadrome.

Around 3,000 armed troops were deployed across Rio to help 30,000 police safeguard the city.

About 1,700 police were at the sambadrome and the spectacle went off without disruption, but a number of shootings were reported in nearby streets after thieves swept through the area assaulting passers-by.