The top diplomats from the Group of 20 largest world economies, including envoys from Russia and China, are meeting in Atlanta as they face deep rifts over multiple wars and other global crises that threaten international security and trade.

U.S. Secretary of State Marco Rubio will chair the gathering Friday and Saturday that will set the stage for a G20 leaders summit hosted by President Donald Trump at his Miami golf club in December.

Serbia 's student movement on Thursday demanded the resignations of top officials in the police, intelligence agencies and the judiciary as they prepare to take power after a historic election win last weekend against former strongman leader Aleksandar Vucic.

The students at a news conference also urged Serbia's election authorities to officially declare the final results of Sunday's ballot without delay after a rerun at some 50 polling stations next Sunday, so that a new Parliament and government can be formed.

Spain's second high-speed rail disaster this year, in which one train struck another from behind, killing 69 people, has raised fresh concerns about the safety of the country's rail network ahead of a national election.

Search teams with sniffer dogs continued to look for victims on Thursday, a day after the collision in central Spain. Cranes shifted the carriages as police and soldiers picked through the wreckage strewn down the gravel slope where at least three train carriages were tossed by the impact.

Humanitarian aid is poised to roll into the stricken city of Oleshky on Friday, a Ukrainian official said, as a localized ceasefire between Russia and Ukraine stretched into a third day and military units cleared away landmines.

Moscow and Kyiv have observed the truce in and around the devastated southern Ukrainian city since Tuesday, despite remaining locked in war since Russia's all-out invasion of its neighbor more than 4 ½ years ago. Previous efforts to secure ceasefires either never worked out or the truces quickly fell apart.

More than 600 Ukrainian drones were launched toward the Moscow region overnight, with most of them shot down, the Russian capital's mayor said early Thursday as the city hosts a Russia-Africa summit.

The leaders of 22 African countries were at the two-day meeting, according to the Kremlin.

A planned six-day ceasefire in and around a Russian-occupied city in southern Ukraine held for its first day and night, officials said Wednesday, but Moscow and Kyiv continued to batter each other elsewhere.

The localized truce in the devastated southern city of Oleshky began Tuesday and is due to last through Sunday as a humanitarian operation races to get urgently needed food and medicine to about 2,000 remaining residents, as well as evacuate those who want to leave.

Flávio Bolsonaro, the defeated Brazilian presidential candidate, fled his country to Argentina and then Ecuador alongside his wife and two daughters, Argentina's migration authority said on Wednesday. The 45-year-old senator and his family were granted United States visas the day before by the Trump administration.

The move is almost certain to cause a big diplomatic rift between Brazil's newly reelected President Luiz Inácio Lula da Silva and his Argentine counterpart Javier Milei, who traveled to Brazil to take part in Bolsonaro's campaign.

A high-speed train slammed into the rear of another train that had stopped, derailing two cars and killing at least 64 people on Wednesday in central Spain, authorities said.

The central government's office for Castilla La Mancha confirmed the death toll had risen.

The United Nations is set to vote Wednesday on a resolution condemning the decades-long U.S. economic embargo on Cuba as the Trump administration intensifies its campaign to undermine Cuba's socialist government, including by threatening military intervention.

The annual exercise aimed at calling out the U.S. government's "maximum pressure policy" has been put before the U.N. General Assembly for the past 34 years, and each time the resolution has received overwhelming support from the 193 member states. Last year, the vote was 165-7, with 12 abstentions.

Serbian police said on Wednesday that an unidentified assailant attacked a guard with knives outside the Israeli Embassy in Belgrade and was killed just after midnight.

Interior Minister Ivica Dacic said that police were treating the incident as a "terrorist attack" and had raised the terror threat to the highest level and stepped up police presence at key locations.