Russia-Ukraine live updates: Fox News cameraman killed in Ukraine; European leaders traveling to Kyiv

BERLIN — Three European leaders traveled on Tuesday to the besieged Ukrainian capital to meet with the country’s president, Volodymyr Zelensky, and to pledge the European Union’s “unequivocal support” and offer financial assistance.

The dramatic visit, as Kyiv went under a curfew in response to renewed Russian attacks, was made by the prime ministers of Poland, Slovenia and the Czech Republic, who crossed into Ukraine by train.

They would be the first foreign leaders to enter the capital since Russia’s attack began 20 days ago. Their visit unfolded against the backdrop of intensifying missile strikes on Kyiv, which killed at least four people Tuesday, according to the mayor, Vitali Klitschko, who placed the city under a 35-hour curfew in light of what he described as a “difficult and dangerous” moment.

NATO Secretary General Jens Stoltenberg warned Tuesday that Russia may be preparing to use chemical weapons as part of a false flag attack.

The remarks, made at a news conference in Brussels, come as concern mounts that Russia’s unsubstantiated claims about bio weapons could signal the use of chemical weapons in the war.

“Any use of chemical weapons will be a violation of international law,” Stoltenberg said. “We call on Russia not to use chemical weapons.”

Asked about China’s role in the war in Ukraine, Stoltenberg said Beijing should “join the rest of the world” in condemning the invasion “strongly.”

Stoltenberg will meet Wednesday with NATO defense ministers for an extraordinary summit. He said the 30-member alliance will discuss longer-term plans to bolster the alliance’s eastern flank in response to the Russian invasion of Ukraine.

This new posture could include substantially more forces on land, as well as a strengthening of air and missile defense, the NATO chief said, as well as “more and larger” military exercises.

It’s going to be a busy few weeks on the International Space Station.

Tuesday morning, a pair of NASA astronauts are scheduled to step outside the station for a spacewalk. Next week, Russia is flying three more cosmonauts to the station. By the end of the month, NASA astronaut Mark Vande Hei and two Russian colleagues are to fly back to earth on a Russian Soyuz spacecraft. And a few hours later, a group of private astronauts is scheduled to launch on a SpaceX rocket for a week-long visit to the station.

Russia’s invasion of Ukraine has heightened tensions between the United States and Russia to levels not seen since the Cold War. But that has not affected the countries’ partnership in space, which has endured for more than two decades — at least for now.

“All these activities have continued for 20 years, and nothing has changed in the last three weeks,” Joel Montalbano, NASA’s space station program manager, said at a briefing Monday. “We’re aware of what’s going on, but we are able to do our jobs to continue operations.”

Oil prices swung lower Tuesday and U.S. stocks rallied in morning trading as investors reckoned with renewed coronavirus lockdowns in China and more cease-fire talks between Russia and Ukraine against an increasingly battle-scarred backdrop.

Several of China’s industrial hubs have been hit with business and travel restrictions as the country grapples with its worst coronavirus outbreak since 2020, with daily cases doubling on Tuesday, according to Chinese authorities. The resurgence, in a country that has taken a “zero tolerance” approach to the virus, has sparked fears of major slowdown in one of the world’s biggest economic engines, as well as worries about an even more snarled global supply chain.

For the first time in about two weeks, oil prices were trading below $100 per barrel. Brent crude, the international benchmark, shed more than 7.8 percent to roughly $98.50 a barrel. West Texas Intermediate crude, the U.S. benchmark, was trading 8.2 percent lower, around $94.50.

“The resurgence in [Chinese coronavirus] cases has provided a stark reminder that the pandemic is still lingering,” Russ Mould, investment director at AJ Bell, said Tuesday in comments emailed to The Washington Post. “Investors might have become too complacent over the risks of lockdowns returning once again.”

Despite the tensions, U.S. stocks opened higher, with the Dow gaining 300 points, more than 0.9 percent, shortly after the opening bell. The S&P 500 climbed 0.8 percent, while the tech-heavy Nasdaq advanced 1 percent.

Hong Kong’s Hang Seng Index cratered more than 5.7 percent, while the Shanghai Composite closed nearly 5 percent lower. European indexes were broadly negative in midday trading, with the benchmark Stoxx 600 index sliding 1 percent.

For nearly 30 years, Russian citizens have had the freedom to travel internationally without government permission, a departure from strict Soviet-era policies lifted in the early 1990s. But in the weeks since Russia mounted its assault on neighboring Ukraine, the conflict has had ripple effects on the international mobility of Russian people around the world.

Dozens of countries have closed their airspace to Russian flights, and Russia, reciprocally, has banned incoming flights from a number of other nations. Many of those affected by these obstacles had been hoping to reunite with their loved ones — and their reunions have been indefinitely, painfully deferred.

Globally, thousands of Russians have been displaced. Some 15,000 tourists from Russia (and 2,000 from Ukraine) were recently stranded in the Dominican Republic because of travel restrictions. Several thousand more Russian and Ukrainian tourists have been unable to return home from Egypt.

Russia is ramping up efforts to “subvert Ukrainian democracy” by installing its own mayors and seeking to stage a referendum in the Ukrainian city of Kherson in a bid to establish the Russian-occupied area as a “breakaway republic,” Britain’s Defense Ministry said Tuesday in an intelligence update.

The ministry said Russian President Vladimir Putin is tightening political control by replacing the Ukrainian mayor of Melitopol, Ivan Fedorov, with one of Russia’s own.

Fedorov was allegedly abducted by Russian soldiers last week, an act that Ukrainian President Volodymyr Zelensky branded “a crime against democracy.”

The intelligence update reported “multiple demonstrations” in the cities of Kherson, Melitopol and Berdyansk — all of which are occupied by Russian forces. In Kherson, Russian troops fired shots into the air to try to disperse crowds of peaceful protesters.

Yevhen Matveyev, the mayor of Dniprorudne in southern Ukraine, was also reportedly abducted by Russian troops, the update said.

In an interview with the “BBC Breakfast” program Tuesday, James Cleverly of Britain’s Foreign Office said Russia’s “plan of attack is not working.” As a result, more civilian areas are coming under fire, he said.

He also referred to a recent prediction from a Ukrainian presidential adviser that the war could end in May, saying such an estimate was “incredibly difficult” to make.

Russia has launched more than 900 missiles into Ukraine since the start of the conflict, according to a senior U.S. defense official, who spoke Monday on the condition of anonymity under ground rules set by the Pentagon. Last week, the Pentagon put the figure closer to 700.

Russian armed forces “still have a lot of capability left to them,” the official said Monday. “We would assess their available combat power as just under 90 percent.”

Annabelle Timsit contributed to this report.

More than 3 million people have fled Ukraine since Russia’s invasion nearly three weeks ago, the International Organization for Migration (IOM), a United Nations agency, said Tuesday.

This grim milestone marks a new chapter in a conflict that U.N. officials have called “the fastest growing refugee crisis in Europe since World War II.”

The number of people fleeing Ukraine has continued to increase, although fighting and shelling inside the country has made movement out more difficult. There were more than 1.5 million Ukrainian refugees 10 days ago; 2.5 million Ukrainian refugees on Friday; 2.8 million on Monday; and now, 3 million. Most of these refugees are fleeing to neighboring countries, particularly Poland. Among the 3 million, the agency said, are 157,000 third-country nationals.

António Vitorino, the IOM’s director general, said the conflict has “uprooted” 3 million lives and called for it to end.

James Elder, a spokesperson for UNICEF, the U.N.'s child protection agency, said Tuesday that 1.5 million Ukrainian children — half the IOM’s total number of refugees — have become refugees since the start of the conflict. That means 55 children become refugees every minute, Elder said, or nearly one per second.