New York  - The Israel-Hamas fighting has inflicted a terrifying and psychological impact on the civilian population in Gaza Strip, particularly on children and their parents, the UN said Wednesday.

The Palestinian Health Ministry updated at the same time the number of casualties, as of Tuesday, in the fighting that erupted on December 27 with heavy Israeli airstrikes against targets in Gaza. It said 971 have been killed, of whom 311 are children and 76 women.

A total of 4,416 people have been injured, of whom 1,549 are children and 652 women, the ministry said.

Four Israelis have been killed since the start of the fighting, the UN said. Israeli officials said Tuesday that 13 Israelis have been killed, including three civilians.

John Holmes, the UN coordinator for humanitarian operations at UN headquarters in New York, used the figures from the ministry to highlight the destructive war in which both Israel and Hamas militants have been accused of violating international humanitarian law.

"The situation for the civilian population in Gaza is terrifying and its psychological impact felt particularly by children and their parents, who felt helpless and unable to protect them," Holmes told a UN Security Council meeting.

"It is a situation from which civilians have only minimal respite, three hours a day, with no escape as borders and crossings remain closed," Holmes said.

"Only a ... fully respected ceasefire will spare the civilian population from these horrors," he said. "And even then, their need for assistance will remain both urgent and overwhelming."

The UN said the Palestinians in Gaza have been under siege for the past 18 months with the closure of crossings by Israel.

The UN Children's Fund said by its own estimate that more than 300 children have been killed and 1,500 others injured by the fighting.

"Each day more children are being hurt, their small bodies wounded and their young lives shattered," UNICEF director Ann Veneman said.

UNICEF said children, who constitute a majority of the 1.5 million-population in Gaza, and their families are trapped by the fighting. Israel and Hamas are now engaged in battle close to centers of residential areas, posing more threats to Palestinian civilians. (dpa)