Seven people from Birmingham have gone on trial accused of racially-motivated violence in the city in 2005.
CCTV footage played to the court showed men arming themselves
Birmingham Crown Court was told that Asians were deliberately targeted in a night of disturbances in Lozells.
Adrian Redgrave QC, prosecuting, said a rumoured attack on a black girl of 14 had sparked some of the violence.
Three defendants are charged with attempted murder, five with riot, one with robbery, two with wounding and four with racially-aggravated damage.
The court was told it had been impossible to establish whether there was any substance to the rumour that the girl had been attacked.
Tension between the city's black and Asian communities soon turned to violence, said Mr Redgrave.
The jury was shown video footage of gangs of men, many of them black and Asian, arming themselves and starting to attack the police and passers-by.
One defendant denies the attempted murder of Naeem Mir.
Two other men are charged with attempting to murder Jatinder Singh Kulaur.
A youth of 15, who cannot be named, is charged with rioting.
The trial is expected to last up to six weeks.