乌克兰政局动荡

But first in Ukraine, the shooting down of a government helicopter has highlighted fears that the crisis in the country is escalating. Kiev believes separatists in the east use Russian weaponry to bring down the copter near Sloviansk, killing 14 soldiers and a high ranking general. Now the White House has expressed its concerns that pro-Russian rebels are still getting advanced weapons from outside the country. We'll hear from our correspondent in Washington in a moment. But first, Mark Lowen in Donetsk reports on the crash.

This is a significant loss of life for the Ukrainian military and a major blow as Kiev pursues what it calls its anti-terror operation here. The helicopter was shot down by rebel fighters as it transported troops to a military base around the town of Sloviansk. Speaking to Parliament, Ukraine's acting President, Olexandr Turchynov, said 14 troops were killed including an army general and that his nation was under attack.