A UN agency that runs schools and social services for Palestinians is facing calls to sack employees using social media to celebrate attacks on Israelis.

Facebook posts by UN staff have included photographs showing blood- drenched knives held by Palestinian men and women in keffiyeh scarves, throwing stones at Israel’s defence forces.

Almost two dozen UN employees have been exposed for publishing their support for a recent bout of stabbing attacks by Palestinians that targeted Israelis.

UN Watch, a Geneva-based watchdog, has called on the body, United Nations relief and works agency (Unrwa), to dismiss those who have posted the hate-filled messages.

Hillel Neuer, the director of UN Watch, said incitement to hatred, particularly by teachers, would only contribute to violence in the Middle East.