LEFTERIS PITARAKIS

A suicide bomber affiliated with the Islamic State group detonated a bomb in a historic district of Istanbul popular with tourists Tuesday morning, killing at least 10 people — nine of them German tourists — and wounding 15 others, Turkish officials said.

Two female assailants opened fire at the U.S. Consulate in Istanbul on Monday and at least six Turkish security forces were killed elsewhere in a day of heavy violence in Turkey, where a government crackdown has targeted Islamic State militants, Kurdish rebels and far-left extremists.