The award-winning journalist was killed while covering clashes between Afghan troops and the Taliban in Spin Boldak district of Kandahar city.
Based in Mumbai, Siddiqui had received the Pulitzer Prize as part of the Photography staff of Reuters news agency.
Indian-origin journalist wins Pulitzer Prize for exposing China's vast infrastructure for detaining Muslims
Rajagopalan's Xinjiang series won the Pulitzer Prize in the International Reporting category.
BuzzFeed News won its first Pulitzer, in international reporting, for a series by Megha Rajagopalan, Alison Killing and Christo Buschek.