Israeli forces shelled a house in the Gaza Strip which they had moved around 110 Palestinians into 24 hours earlier, the UN quotes witnesses as saying.
The UN Office for the Coordination of Humanitarian Affairs (OCHA) called it "one of the gravest incidents" since the beginning of the offensive.
The shelling at Zeitoun, a south-east suburb of Gaza City, on 5 January killed some 30 people, the report said.
Israel 'shelled civilian shelter'
Tens of thousands of displaced Palestinians in Gaza, surrounded by tents and debris, are suffering through...
Pope Leo decried conditions for Palestinians in Gaza in his Christmas sermon, in an unusually direct...
