On 29 March 2002 the Israeli Defence Forces (IDF) launched a new offensive, Operation Defensive Shield, in Palestinian residential areas. According to the IDF, the purpose of the offensive, like the incursions into refugee camps which preceded it in March and the occupation of the West Bank which followed in June, was to eradicate the infrastructure of "terrorism", in particular following Palestinian armed groups' killing of 40 Israeli civilians between 1 March and 1 April.