A Ukrainian fighter plane has been shot down by pro-Russian rebels over eastern Ukraine as government forces entered deep inside the rebel-controlled city of Luhansk, according to the Ukrainian military.
A military spokesman said the Mig-29 fighter jet was shot down overnight, and the pilot ejected and was taken to a secure place.
Government forces have taken a police station in Luhansk, the city on the border with Russia over which the plane was shot down, according to military spokesman Andriy Lysenko. The Ukrainian flag has been raised in the city, which has been under the control of pro-Russian separatists since April.
He added that fresh Russian military equipment has been seen coming into the country from Russia in the past 24 hours, including three Grad missile system, and stated that Russian drones had violated Ukrainian air space on 10 occasions.
In a video posted online this weekend, the leader of the self-proclaimed rebel government in Donetsk, Alexander Zakharchenko, was seen saying Russia was sending new military equipment.
He said the shipment included tanks and some 1,200 trained fighters. Donetsk, the main rebel-held city, is several hours drive west of Luhansk, and is also suffering through fighting including frequent shelling.
Ukraine crisis: Russian 'aid' convoy
Ukraine crisis: Russian 'aid' convoy
1/11 Ukraine crisis
Drivers of the first trucks of the Russian aid convoy parked in the city of Luhansk on 22 August
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An employee inspects the contents of a truck with Russian humanitarian aid in Mariupol, Ukraine on 22 August 2014
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The convoy nearing the border before it parked at a camp in Russia
4/11 Ukraine crisis
Russian convoy carrying humanitarian aid for residents in rebel eastern Ukrainian regions moving along a road in the city of Voronezh, about 530 km from Moscow, Russia
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An Ukrainian border guard checks passing cars at a checkpoint of Pletnyovka, Kharkiv region on Ukraine-Russia border, where Russian humanitarian convoy is to cross the border
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Ukrainian border guards stand at the Ukrainian-Russian border crossing
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Trucks of a Russian convoy carrying humanitarian aid for Ukraine are parked at the military air base outside Voronezh
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Drivers of a Russian convoy of trucks carrying humanitarian aid for Ukraine take a rest on a side of a road near the city of Yelets
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An Ukrainian soldier stands guard at a checkpoint of Pletnyovka, Kharkiv region on Ukraine-Russia border, where Russian humanitarian convoy is to cross the border
10/11 Ukraine crisis
A Russian convoy carrying humanitarian aid for residents in rebel eastern Ukrainian regions moves along a road about 50 km from Voronezh, Russia, 14 August 2014. The convoy continues to advance through Russian territory after a one-day stop in Voronezh in full coordination with and under the aegis of the Red Cross, according to Russian authorities
11/11 Ukraine crisis
The Russian convoy carrying humanitarian aid in the Voronezh region of Russia en route to Ukraine
Fighting in Ukraine has escalated since the insurgency arose in April, with government troops steadily taking back rebel-held territory in the east.
German Foreign Minister Frank-Walter Steinmeier has spoken out ahead of today's meeting of foreign ministers from Ukraine, Russia, Germany and France. "We urgently need new political impetus now, otherwise we run the risk of stalling, regressing again or entering another, worse spiral of escalation," he said in a statement.
Steinmeier said the meeting in Berlin would be used to explore ways to re-start the political process, adding that this meant above all coming up with a plan on how to bring about a sustainable ceasefire and a framework for effective border controls.
Video: Fighting has continued in Ukraine
"Only in this way can eastern Ukraine come to rest and Kiev can start a national dialogue again to integrate the people in the east appropriately," he said.
The latest fighting comes as a Russian aid convoy is waiting on the Ukrainian border for clearance to bring supplies to suffering civilians in the region. The International Committee of the Red Cross, which would have responsibility for distributing the aid, on Saturday said the main holdup was a lack of security guarantees from all sides in the conflict.