Oslo police have said that 40,000 people gathered in Youngstorget Square, central Oslo, to sing a song that Breivik hates as his trial continues. Protesters including many children streamed into the square wearing colourful raincoats and waving Norwegian flags and roses, which have become the symbol of Norway's peaceful reaction to the horrifying killings last summer. Breivik is known to think that "Children of the Rainbow" by Norwegian folk singer Lillebjoern Nilsen is communist indoctrination. Nilsen himself led the chorus as the crowd sang along. Also in attendance were culture ministers of the Nordic countries. After the song the crowd walked slowly together, still singing, to the courthouse to add their roses to the piles of flowers already lining the security barriers outside in memory of Breivik's victims. Breivik was inside listening to testimonies from survivors of his attacks in Oslo and the island of Utøya. [Photographs: via Amnesty, and courtesy of @tgangstad]