The Kum Kapu demonstration occurred in the Kumkapı district of Constantinople on July 27, 1890. It ensued in skirmishing where several persons, including a police officer were killed. Many more were wounded. The cause of the demonstrations were "..to awaken the maltreated Armenians and to make the Sublime Porte fully aware of the miseries of the Armenians."
Read more about Kum Kapu Demonstration: Background, July 27, 1890, Result