Sen. John McCainJohn McCainGraham: There are 'no good choices left' with North Korea Graham: North Korea shouldn't underestimate Trump Give Trump the silent treatment MORE (R-Ariz.) said there would be "hell to pay" if Russia or Russian separatists were involved in the crash of a Malaysian airplane over eastern Ukraine.
"It has the earmarks of a tragic mistake made by someone who had the capability to shoot down an aircraft," he said. "And we know at least from the last few couple of weeks that could be Russian or separatist Russian capability. If that is true, this is really, really something that commands our attention to bring this kind of thing to a halt."
If Russia or Russian separatists were involved in the incident, McCain said, "I think there is going to be hell to pay and should be."
Still, McCain said people should not yet leap to conclusions, predicting that answers would come in the next few hours.
"To leap to conclusions could be very embarrassing and really inappropriate until we have more information," McCain said on MSNBC. "But there have been, as you mentioned, previous instances of shoot down of Ukrainian aircraft."
"It has the earmarks — and I'm not concluding — but it has the earmarks of a mistaken identification of a aircraft that they may have believed was Ukrainian,” he said. "If that is true, this is a horrible — if it is true — it is a horrible tragedy."
A number of news agencies have reported that the Boeing 777 carrying nearly 300 people was shot down in Eastern Ukraine. Ukraine's President Petro Poroshenko told The Associated Press that his country's military did not shoot down any "airborne targets."