About 200 people marched through the downtown core Saturday, before ending up on Parliament Hill, to protest the government's stance on the conflict between Israel and Hamas.
Chanting "shame, shame Harper" and "free, free Palestine" the demonstrators gathered at the Human Rights Monument on Elgin street before moving to Parliament Hill.
The march comes amid fresh fighting in the war-torn region.
After a 72-hour ceasefire ended, hostilities resumed between Hamas and Israel, as rocket attacks by Hamas prompted a series of new airstrikes by Israel.
Hamas officials say Israeli airstrikes hit houses and mosques as well as its warehouses and training sites.
A Palestinian health official says three bodies were found under the ruins of the al-Qassam mosque in Gaza, including that of a senior Hamas official.
Egyptian-brokered talks between Israel and Hamas on a new border deal for Gaza were thrown into doubt after senior officials said an Israeli team would not rejoin negotiations in Cairo unless rocket fire from Gaza stops.
With files from CTV Ottawa and The Canadian Press