What do we know about Ukraine's use of Turkish Bayraktar drones?

During Russia's war on Ukraine, video footage has circulated on the internet showing the Turkish combat drone Bayraktar TB2 successfully striking the Russian army. But as so often during heightened conflicts, it is hard to distinguish between factual events and misinformation – some videos of the drone attacks have already been exposed as the latter. Given the chaotic events on the ground, it is almost impossible to assess how often and how successfully Ukraine has utilised its Turkish drones so far, Mauro Gilli, senior researcher in military technology and international security at ETH Zurich, told Al Jazeera. "There have been some video footages allegedly showing the employment of the TB2. Of course, information at this point is fragmented, and it needs to be taken with caution. "We do know that Ukraine bought some TB2 over the past years and that Turkey and Ukraine signed an agreement for the production within Ukrainian borders of the TB2 – but, as far as I know, production had not started yet.