Kiev (AFP) - Heavy rockets that killed at least 30 people on Saturday in Ukraine's government-held port of Mariupol were fired from territory controlled by pro-Russian rebels, international monitors said.
The Organization for Security and Co-operation in Europe (OSCE) said its inspection team concluded that "the Grad rockets originated from a northeasterly direction... and the Uragan rockets from an easterly direction, both controlled by the 'Donetsk People's Republic'."
The self-proclaimed separatist region's leader had earlier announced the launch of a major new offensive against Mariupol but did not acknowledge direct responsiblity for the rocket attacks.
"Today, we launched an offensive against Mariupol," Russia's RIA Novosti news agency quoted Donetsk separatist leader Alexander Zakharchenko as saying.
But he added a few hours later that his forces were still "saving their strength" and had "conducted no active operations in Mariupol."
The OSCE said its Special Monitoring Mission (SMM) confirmed 19 rocket impacts around the city "and is certain there are more".
"The SMM observed in an area of 1.6 kilometres by 1.1 kilometres, including an open market, multiple impacts on buildings, retail shops, homes and a school," the OSCE said in a spot report.
"The SMM observed cars on fire and windows facing the northeastern side of a nine-storey building shattered," it added.