(WRIC / AP) – Russian troops invaded Ukraine Thursday with air and missile strikes in Kyiv and other cities. Russian President Vladimir Putin warned other countries that any attempt to interfere with the Russian action would lead to “consequences you have never seen.” According to Ukrainian officials, Russian troops moved in from the north, east and south. Explosions were heard before dawn as world leaders decried the invasion that could cause massive casualties and topple Ukraine’s democratically-elected government.

Damaged radar, a vehicle and equipment are seen at a Ukrainian military facility outside Mariupol, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Sergei Grits)
People gather in a shelter during Russian shelling, in Mariupol, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Evgeniy Maloletka)
A woman holds her baby inside a bus as they leave Kyiv, Ukraine, Thursday, Feb. 24, 2022. Russia launched a wide-ranging attack on Ukraine on Thursday, hitting cities and bases with airstrikes or shelling, as civilians piled into trains and cars to flee. (AP Photo/Emilio Morenatti)
Ukrainian military track burns at an air defense base in the aftermath of an apparent Russian strike in Mariupol, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Evgeniy Maloletka)
People try to get on a bus as they leave Kyiv, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Emilio Morenatti)
Joe Biden
President Joe Biden speaks about the Russian invasion of Ukraine in the East Room of the White House, Thursday, Feb. 24, 2022, in Washington. (AP Photo/Alex Brandon)
A woman reacts as she waits for a train trying to leave Kyiv, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Emilio Morenatti)
A view of Ukraine’s Motherland Monument in Kyiv Sunday, Feb. 13, 2022. The threat of war has shredded Ukraine’s economy, and many Ukrainians are asking why they are the ones suffering instead of Russia. The pressure from Russian troops has closed international offices, canceled flights and caused hundreds of millions of dollars in investment to dry up within weeks. (AP Photo/Efrem Lukatsky, File)
A food delivery man leaves an exchange office with screen showing the currency exchange rates of U.S. Dollar and Euro to Russian Rubles in Moscow, Russia, Thursday, Feb. 24, 2022. The Russian ruble nosedived at the news of the Russian attack on Ukraine, although it has recovered some of the losses thanks to a massive intervention by the country’s Central Bank. (AP Photo/Alexander Zemlianichenko Jr)
A shelter construction covers the exploded reactor at the Chernobyl nuclear plant, in Chernobyl, Ukraine, Tuesday, April 27, 2021. Ukrainian authorities decided to use the deserted exclusion zone around the Chernobyl power plant to build a repository where Ukraine could store its nuclear waste for the next 100 years. (AP Photo/Efrem Lukatsky)
Smoke and flame rise near a military building after an apparent Russian strike in Kyiv, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Efrem Lukatsky)
Police officers inspect the area after an apparent Russian strike in Kyiv Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Emilio Morenatti)
A man and woman stand next to fragments of military equipment on the street in the aftermath of an apparent Russian strike in Kharkiv in Kharkiv, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Andrew Marienko)
Women show posters in support of Ukraine as they attend a demonstration along the street near the Russian embassy to protest against the escalation of the tension between Russia and Ukraine in Berlin, Germany, Tuesday, Feb. 22, 2022. (AP Photo/Markus Schreiber)
Damaged radar arrays and other equipment are seen at a Ukrainian military facility outside Mariupol, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Sergei Grits)
A Ukrainian serviceman stands at his position at the line of separation between Ukraine-held territory and rebel-held territory near Svitlodarsk, eastern Ukraine, Wednesday, Feb. 23, 2022. (AP Photo/Evgeniy Maloletka)
The aftermath of an explosion in Kyiv, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Efrem Lukatsky)
Traffic jams are seen as people leave the city of Kyiv, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Emilio Morenatti)
People walk past the aftermath of Russian shelling in Kyiv, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Efrem Lukatsky)
A woman and child peer out of the window of a bus as they leave Sievierodonetsk, the Luhansk region, in eastern Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Vadim Ghirda)
This photo shows a view of the city of Kyiv, Ukraine, Thursday, Feb. 24, 2022. (AP Photo/Emilio Morenatti)
A Ukrainian soldier talks with her comrades sitting in a shelter at the line of separation between Ukraine-held territory and rebel-held territory near Svitlodarsk, eastern Ukraine, Wednesday, Feb. 23, 2022. U.S. President Joe Biden announced the U.S. was ordering heavy financial sanctions against Russia, declaring that Moscow had flagrantly violated international law in what he called the “beginning of a Russian invasion of Ukraine.” (AP Photo/Evgeniy Maloletka)
A woman stands in front of TV screens broadcasting the news that Russian troops launched their attack on Ukraine, in Hong Kong Thursday, Feb. 24, 2022. (AP Photo/Vincent Yu)
Russian President Vladimir Putin addresses the nation in the Kremlin in Moscow, Russia, Monday, Feb. 21, 2022. (Alexei Nikolsky, Sputnik, Kremlin Pool Photo via AP)
Ukrainian servicemen scan belongings of people crossing from Ukrainian government controlled areas to pro-Russian separatists’ controlled territory in Stanytsia Luhanska, the only crossing point open daily, in the Luhansk region, eastern Ukraine, Tuesday, Feb. 22, 2022. (AP Photo/Vadim Ghirda)
Russian armored vehicles are loaded onto railway platforms at a railway station in the region not far from the Russia-Ukraine border, in the Rostov-on-Don region, Russia, Wednesday, Feb. 23, 2022. U.S. (AP Photo)
People attend a ceremony to mark the anniversary of the withdrawal of Soviet troops from Afghanistan in the city of Kyiv, Ukraine, Tuesday, Feb. 15, 2022. (AP Photo/Emilio Morenatti)
The app of the Russian government newspaper is displayed on an iPhone screen showing Russian President Vladimir Putin during his speech in the Kremlin in Moscow, Russia, Tuesday, Feb. 22, 2022. As the West sounds the alarm about the Kremlin ordering troops into eastern Ukraine and decries an invasion, Russian state media paints a completely different picture. It portrays the move as Moscow coming to the rescue of war-torn areas tormented by Ukraine’s aggression and bringing them much-needed peace. (AP Photo/Alexander Zemlianichenko Jr)
Ukrainians gather for “Mariupol is Ukraine” in Mariupol, Ukraine, Tuesday, Feb. 22, 2022. (AP Photo/Sergei Grits)
Nancy Pelosi, Eric Swalwell, Adam Schiff
Speaker of the House Nancy Pelosi, D-Calif., flanked by Rep. Eric Swalwell, D-Calif., left, and House Intelligence Committee Chairman Adam Schiff, D-Calif.,holds a news conference at the Capitol in Washington, Wednesday, Feb. 23, 2022. Pelosi says the Russian attack on Ukraine is “an attack on democracy.” Pelosi vowed Wednesday the U.S. is united with world leaders in swiftly imposing sanctions on Putin’s aggression and ensuring financial support for the independent nation. (AP Photo/J. Scott Applewhite)
A woman, her fingernails painted in the colors of the Ukrainian national flag, takes part in a protest against the escalation of the tension between Russia and Ukraine, near the Russian embassy in Berlin, Germany, Tuesday, Feb. 22, 2022. (AP Photo/Markus Schreiber)
In this 2020 file photo, activists burn flares during a protest against joint patrols in Donbas by Ukrainian Armed Forces, OSCE Special Monitoring Mission and rebels, near the residence of Ukrainian President Volodymyr Zelenskiy, outside Kyiv, Ukraine, Thursday, Sept. 10, 2020. (AP Photo/Sergei Grits)
A Ukrainian serviceman walks inside a destroyed house near the frontline village of Krymske, Luhansk region, in eastern Ukraine, Saturday, Feb. 19, 2022. Ukrainian President Volodymyr Zelenskyy, facing a sharp spike in violence in and around territory held by Russia-backed rebels and increasingly dire warnings that Russia plans to invade, on Saturday called for Russian President Vladimir Putin to meet him and seek a resolution to the crisis. (AP Photo/Vadim Ghirda)