Flights avoiding air space in Ukrainian-Russian war zone after Malaysia plane crash

NEW YORK (WABC) -- Before Thursday, air space over Ukraine was not restricted, but immediately after the suspected missile strike that brought down a Malaysian Airlines passenger jet, there was a significant change in the skies.

The site "Flight Radar 24" shows flights now avoiding airspace over the Ukrainian-Russian border.

Large parts of Ukraine's border with Russia had been off-limits for all U-S commercial airlines for months. Intelligence has shown an increasing risk to ANY aircraft flying along the Eastern Border where the separatist violence and weaponry to wage it has been growing.

As Malaysian Air Flight 17 cruised at 33,000 feet above Ukraine, its pilots and passengers probably never thought for a second about the escalating violence below.

But as far back as April, the U.S. government through the FAA had banned all U.S. carriers from flying through airspace in part of Ukraine's war-torn border with Russia:

"You get to a point where an air carrier would say wait a minute not a good idea to fly in this area," said pilot and aviation attorney Brian Alexander.

Alexander, whose firm Kreindler and Kreindler has represented families in nearly every air disaster in the last 30 years, says there were a lot of red flags to avoid this troubled airspace.

"It begs the question why wouldn't you avoid it entirely out of an abundance of caution. I think these questions will be asked in the coming days," said Alexander.

Authorities say that 24 hours earlier, a Ukrainian fighter jet was shot down by a Russian military plane. And earlier this week, a Ukraine military transport plane was shot down by a missile fired from Russian territory:

"We know there have been deliberate provocative actions by what is believed were by Russians in the past days and weeks to shoot down Ukrainian aircraft. Could they have mistaken this Malaysian Jet for a Ukrainian aircraft? It is quite possible," said ABC News military analyst Col Stephen Ganyard.

Both the Russian government and pro-Russian rebels deny that they brought the plane down. The debris field seems to indicate it was something external, that the on-going conflict five miles below caused the catastrophe above.

"This looks like it's very concentrated like something hit it from outside, blew it up and it fell directly down," said former national security adviser Richard Clarke.

Military experts say it won't take long to determine if a missle brought down flight 17, even what kind of missile. The recent downing of Ukrainian military planes shows an increasing sophistication in arms of the pro-Russian rebels.