Vienna/Kiev, Nov 4 : The Vienna-based International Atomic Energy Agency (IAEA) said it did not find any indications of undeclared nuclear activities and materials at three locations it had inspected in Ukraine. "Our technical and scientific evaluation of the results we have so far did not show any sign of undeclared nuclear activities and materials at these three locations," IAEA Director-General Rafael Grossi said in a statement on Wednesday. A team of IAEA inspectors also collected environmental samples for analysis at the inspected locations and soon will report on their results, Grossi said. The UN nuclear watchdog sent its experts to the war-torn nation at the request of the Ukrainian government after Russia made allegations about activities related to the possible production of "dirty bombs" in certain locations. The IAEA team inspected the Institute for Nuclear Research in Kiev, as well as two facilities in Dnipropetrovsk region -- the Eastern Mining and Processing Plant, and Production Association Pivdenny Machine-Building Plant. In his nightly address to the nation on Thursday, Ukrainian President Volodymyr Zelensky said: "We had invited the IAEA to check, we gave them full freedom of action at the relevant facilities, and we have clear and irrefutable evidence that no one in Ukraine has created or is creating any 'dirty bombs'. "And the only thing that is dirty in our region now is the heads of those in Moscow who, unfortunately, seized control of the Russian state and are terrorizing Ukraine and the whole world." Dirty bombs contain radioactive material, such as uranium, which is scattered through the air when its conventional explosive detonates. They do not need to contain highly refined radioactive material, as is used in a nuclear bomb, which makes them cheaper and easier to manoeuvre. /IANS