Ukraine says air force jet downed by Russian missile

A Russian jet shot down a Ukrainian air force SU-25 plane that was on military operations over eastern Ukraine, where government forces are fighting to quell a pro-Russian rebellion, a Ukrainian military spokesman said on Thursday.

Ukrainian troops were also fired upon by missiles from a village just inside Russia, Andrei Lysenko, a spokesman for Ukraine's Security Council, said Thursday. The plane was brought down on Wednesday night by a rocket strike and the pilot safely ejected, Lysenko said.

The allegations, which Russia's Defense Ministry declined to comment on, are the strongest to date by Ukraine of direct Russian military involvement in the conflict. It was the third reported incident this week in which a Ukrainian plane has been hit by a missile.

Kiev has said that an An-26 military transporter was brought down last Monday, probably by a missile fired from Russia, either from the air or from the ground. Two of the eight people on board that plane were killed, the Ukrainian military said. 

On Wednesday, another SU-25 was hit by a rebel missile, but the pilot brought the plane down successfully with relatively slight damage. Kiev did not allege Russian involvement in that case.

The incidents come against a background of increasingly strident charges by Kiev of direct Russian involvement in the three-and-a-half-month conflict.

Moscow denies orchestrating the rebellion, but Western governments accuse it of failing to curb the violence.

After a day's pause, Ukrainian warplanes on Wednesday resumed overflights in the east where they have been striking at rebels and military equipment, which Kiev says is being brought in from Russia to fortify rebel positions.

Lysenko said five more Ukrainian servicemen had been killed in the past 24 hours, which would bring to more than 270 the number killed since the government launched its operation in April to crush the rebels. Hundreds of civilians and rebels have also been killed. 

On Wednesday, the U.S. slapped tougher sanctions against Russia for its actions in Ukraine, prompting a strong reaction from Russian President Vladimir Putin, who said they will stalemate bilateral relations and hurt not only Russian but also American businesses.

After months of measures that affected only individuals and smaller firms, Washington imposed sanctions on Russia's largest oil producer, Rosneft, its second largest gas producer, Novatek, and its third largest bank, Gazprombank. 

The firms are run by Putin allies who have become wealthy during his tenure. Moscow denounced what it called revenge for events in Ukraine and pledged to retaliate. Putin said the U.S. sanctions would hurt U.S. energy companies and bring relations to "a dead end."

Russian Prime Minister Dmitry Medvedev called the sanctions evil and said they would not "bring anyone to their knees."

Wire services