At least three blasts were heard in the Russian-controlled Donetsk region in eastern Ukraine amid an Easter ceasefire declared by Moscow, Russian state news agency TASS reported, citing local "operative services." Ukraine's forces reported nearly 3,000 violations of Russia's own ceasefire pledge, Ukrainian President Volodymyr Zelenskyy said, adding that Kyiv's forces were instructed to mirror the Russian Army's actions. Russia's Ministry of Defence said Ukraine had broken the Easter ceasefire declared by the Kremlin more than a thousand times, claiming that Ukrainian forces shot at Russian positions 444 times. The ministry also said Kremlin forces encountered more than 900 Ukrainian drone attacks during this time. At least three blasts were heard in the Russian-controlled Donetsk region in eastern Ukraine amid an Easter ceasefire declared by Moscow, Russian state news agency TASS reported, citing local "operative services."

In the early hours of Monday, residents in several Ukrainian cities, including the capital Kyiv, were urged by local authorities to go immediately to nearby shelters due to the threat of drone strikes. The BBC has not independently verified the claims by Kyiv and Moscow. US President Donald Trump - who has been pushing for an end to the war - said late on Sunday that "hopefully Russia and Ukraine will make a deal this week". He gave no further details. Russia launched a full-scale invasion of Ukraine on 24 February 2022, and currently controls about 20% Ukraine's territory, including the southern Crimea peninsula annexed by Moscow in 2014.

Ukraine and Russia have accused each other of breaching an "Easter truce" announced by Russian President Vladimir Putin that Ukraine said was being violated from the moment it started. In a surprise announcement on Saturday, Putin ordered his forces to "stop all military activity" along the front line in the war against Ukraine, citing humanitarian reasons. The 30-hour cessation of hostilities would have been the most significant pause in the fighting throughout the three-year conflict. But just hours after the order was meant to have come into effect, air raid sirens sounded in Kyiv and several other Ukrainian regions, with President Volodymyr Zelenskyy accusing Russia of having maintained its attacks and engaging in a PR stunt. Russia's Ministry of Defence also alleged on Sunday that Ukraine had broken the truce more than 1,000 times.

Former CIA station chief Dan Hoffman joins'Fox News Live' to discuss Russian President Vladimir Putin's announcement of a ceasefire in Ukraine on Easter Day. Ukrainian President Volodymyr Zelenskyy expressed skepticism over Russian President Vladimir Putin's announcement Saturday that Russia would observe a temporary ceasefire during the Easter holiday. After the announcement, Zelenskyy posted on X that air raid alerts were ringing out across Ukraine, adding that Russian attack drones were detected in the skies. "Shahed drones in our skies reveal Putin's true attitude toward Easter and toward human life," he wrote. The Kremlin on Saturday shared a video in which Putin said, "Guided by humanitarian considerations, today from 18:00 to 00:00, from Sunday to Monday, the Russian side declares an Easter truce.'"

James Cameron wasn't near the penguins this time around, but he is extremely familiar with their environment. "When I went to Antarctica myself, I had a Nikon still camera adapted to the cold with special lubricants," he tells Popular Science. "I went to the South Pole and the film shattered in my hand when I tried to change it. I took a video camera, I wrapped it in a heating pack and it [died] in two minutes. I have a good sense of what it takes to take conventional equipment into that environment and survive."

Russia launched eight missiles and 87 drones in an overnight attack on Ukraine on Saturday, causing damage in five regions across the country, the Ukrainian air force said. Air defence units shot down 33 Russian drones while another 36 were redirected by electronic warfare. Damage was recorded in five regions in the south, northeast and east. A Russian missile attack killed one person in Kharkiv, while a drone attack killed another in Sumy, with at least five children among dozens injured. Kharkiv Mayor Ihor Terekhov said 15 residential buildings, a business and an educational facility were damaged in the attack.

This paper presents a novel autonomous drone-based smoke plume tracking system capable of navigating and tracking plumes in highly unsteady atmospheric conditions. The system integrates advanced hardware and software and a comprehensive simulation environment to ensure robust performance in controlled and real-world settings. The quadrotor, equipped with a high-resolution imaging system and an advanced onboard computing unit, performs precise maneuvers while accurately detecting and tracking dynamic smoke plumes under fluctuating conditions. Our software implements a two-phase flight operation, i.e., descending into the smoke plume upon detection and continuously monitoring the smoke movement during in-plume tracking. Leveraging Proportional Integral-Derivative (PID) control and a Proximal Policy Optimization based Deep Reinforcement Learning (DRL) controller enables adaptation to plume dynamics. Unreal Engine simulation evaluates performance under various smoke-wind scenarios, from steady flow to complex, unsteady fluctuations, showing that while the PID controller performs adequately in simpler scenarios, the DRL-based controller excels in more challenging environments. Field tests corroborate these findings. This system opens new possibilities for drone-based monitoring in areas like wildfire management and air quality assessment. The successful integration of DRL for real-time decision-making advances autonomous drone control for dynamic environments.

Unmanned aerial vehicles (UAVs) are becoming more commonly used in populated areas, raising concerns about noise pollution generated from their propellers. This study investigates the acoustic performance of unconventional propeller designs, specifically toroidal and uneven-blade spaced propellers, for their potential in reducing psychoacoustic annoyance. Our experimental results show that these designs noticeably reduced acoustic characteristics associated with noise annoyance.

This highly scalable approach may finally open the skies to a host of commercial drone applications that have yet to materialize. Amazon Prime Air launched in 2022 but was put on hold after crashes at a testing facility, for example. On any given day, only 8,500 or so unmanned aircraft fly in US airspace, the vast majority of which are used for recreational purposes rather than for services like search and rescue missions, real estate inspections, video surveillance, or farmland surveys. One obstacle to wider use has been concern over possible midair drone-to-drone collisions. This prevents most collisions but also most use cases, such as delivering medication to a patient's doorstep or dispatching a police drone to an active crime scene so first responders can better prepare before arriving.

Ukraine has reported dozens of civilian deaths from Russian attacks over the past week, including three killed in a late-night assault on Wednesday in the southeastern city of Dnipro. A child was among the victims of the drone attack, which came hours before high-stakes meetings in Paris due to take place later on Thursday, during which United States Secretary of State Marco Rubio and special envoy to the Middle East Steve Witkoff are to meet French President Emmanuel Macron and other European officials to discuss the conflict. Ukraine's defence and foreign ministers, as well as President Volodymyr Zelenskyy's chief of staff, are also in the French capital for talks with US and European Union delegations, though Kyiv's delegation has not specified who it plans to meet. But as Moscow's self-imposed 30-day ceasefire on energy infrastructure approached its close, talks to achieve a broader ceasefire so far have showed little sign of progress. Russia has stuck to its hardline positions while accusing Ukraine of violating the energy ceasefire, to which Kyiv never agreed.