Israeli troops shot dead dozens of Palestinian protesters on the Gaza border on Monday when the high-profile opening of the U.S. embassy to Israel in Jerusalem raised tension to boiling point after weeks of demonstrations.

In the bloodiest single day for Palestinians since 2014, Palestinian Health Ministry officials said 55 protesters were killed and 2,700 injured either by live gunfire, tear gas or other means.

The bloodshed drew calls for restraint from some countries, including France and Britain, and stronger criticism from others, with Turkey calling it "a massacre."