Police are investigating an alleged racist attack against Portuguese migrant workers after an explosive device containing nails went off in a block of flats in Norfolk.
About 20 people, including four children, escaped injury when three firework explosions damaged a building in Watton. They have been evacuated to a residential centre in Thetford.
The attack follows growing tension between Norfolk's Portuguese community and residents who resent losing jobs to migrant workers. Many of the Portuguese visitors are seasonal workers who come to Norfolk to find work in the farming industry.
A police spokesman said three people had been arrested in connection with the attack and were being questioned yesterday.
The alarm was raised at about 5.30pm on Thursday. It was first thought that a device had been flung through an open first-floor window, but it later emerged that a plastic container packed with fireworks, nails, screws and bolts had been placed on a communal landing on the first floor and set alight.
The spokesman said the attack was being treated as a racist incident because the flats contained Portuguese and British residents. He said the device was not a bomb and that its explosive power was derived from fireworks rather than TNT. He described the evacuation of the residents as a precautionary measure.