was launched on 24 January 2015 by the Donetsk People's Republic, from the village of Shyrokyne around east of Mariupol city limits. Grad rockets fired by separatist forces hit residential areas of Mariupol, killing at least 30 people. A Bellingcat investigative team concluded that the shelling was instructed, directed and supervised by Russian military commanders in active service with the Russian Ministry of Defense. The attack exposed the city's vulnerability to separatist attacks. As a result, in February 2015, Ukrainian forces launched an surprise assault on Shyrokyne, forcing the separatists out from Shyrokyne and neighbouring villages by July 2015. In May 2018, the Crimean Bridge was opened, linking mainland Russia to Crimea, which had been illegally annexed in 2014 in the opening stages of the Russo-Ukrainian War. Russia "dramatically increased" the number of armed vessels in the Kerch Strait in 2018, and cargo ships bound for Mariupol found themselves subject to inspections by Russian authorities, resulting in delays of up to a week. Therefore, Mariupol port workers were put on a four-day week schedule. On 26 October 2018, The Globe and Mail reported that the bridge had reduced Ukrainian shipping from its Azov Sea ports (including Mariupol) by about 25%. 2022 Russian siege and subsequent occupation During the 2022 Russian invasion of Ukraine, Mariupol was a strategic target for Russian forces and their proxies. It came under artillery bombardment the day the invasion began, and was placed under siege by Russian forces. By early March, a severe humanitarian crisis developed in the city, which an aid worker from the Red Cross later described as "apocalyptic", citing severe damage to infrastructure, access to sanitation, and food shortages. The siege was also marked by numerous war crimes committed by Russian forces, most notably Russian airstrikes on a maternity hospital and a drama theater serving as an air raid shelter for hundreds of civilians. By late April, Russian and separatist troops had pushed deep into most of the city, separating the last Ukrainian troops, with the few pockets of Ukrainian troops retreating into the Azovstal Iron and Steel Works, which contains a complex of bunkers and tunnels which could even resist a nuclear bombing. Ukrainian troops in Azovstal held out until 16 May 2022, when its last troops from the Azovstal Steel Plant surrendered and the city fell into Russian control. By the end of the fighting, "as many as 90%" of residential