Danish police are searching for unknown attackers who set fire to the immigration minister's car. Rikke Hvilshoj, her husband and two young children were rescued from their house, which also caught fire as a result of the attack. A group calling itself "Beatte Without Borders" has said it carried out the attack, condemning the government's "racist immigration policy". The minister and other senior politicians have been assigned guards. The attack took place at 0300 local time. Mrs Hvilshoj, 34, was woken up by a "loud bang". When the rescuers arrived, parts of her house were in flames, too. The group that said it carried out the attack sent a statement to various Danish media, which said: "We cannot watch passively, while the official Denmark carries out its racist immigration policy. "That's why we are taking action now." The family has been moved to a secret address. The attack has come as a shock to Denmark's open society where it is not unusual to see ministers and other public figures go shopping, cycle and live their everyday lives among the rest of the population. Justice Minister Lene Espersen says that given the fact that there were children in the house, the attackers could get life imprisonment. The Danish government, which was re-elected in February, has introduced some of Europe's toughest restrictions on immigration. Nevertheless, the centre-right government insists the measures are right and fair.