Inside the UNRWA school:

A United Nations Relief and Works Agency school filled with Palestinian refugees was shelled by Israeli tanks, according to initial reports.

Many of the victims were women and children.

The school was being used as a shelter.

Journalist Sharif Kouddous tweets "heart wrenching scenes."

Reporter William Booth on the scene:

UNRWA spokesman Chris Gunness tweeted that the Israeli army was aware of the location of the shelter.

A CNN cameraman:

Gunness, the UNRWA spokesman, said the military knew the coordinates of the shelter.

The UNRWA has 83 shelters across Gaza. Currently, 141,338 Palestinian civilians are displaced.