The Olympic torch has arrived in Rio de Janeiro by boat after a three month tour of Brazilian cities. The mayor of Rio, Eduardo Paes, carried the torch on its first few laps through the city centre as it makes its way to the famous Maracana Stadium for the opening ceremony on tomorrow. But there were chaotic scenes later in the north of the city when the torch relay was challenged by hundreds of demonstrators angry at the high cost of hosting the Games. Riot police used tear gas and pepper spray to disperse the crowd. Brazil is in the grip of a deep recession and political crisis, and further protests are expected ahead of the Olympic opening ceremony. Organisers say more than a million tickets remain unsold.