JACKSONVILLE, Fla. -

Many questions remain after a commercial jet crashed in Eastern Ukraine. All 298 people on board were killed.

President Barack Obama delivered a strongly worded statement at the White House Friday about the crash of Malaysia Airlines Flight 17.

"... men, women, children, infants who had nothing to do with the crisis in Ukraine. Their deaths are an outrage of unspeakable proportions,” Obama said.

The president said at least one American is among the victims. The plane fell out of the sky Thursday, on its way from Amsterdam to Kuala Lumpur, and U.S. intelligence officials believe pro-Russia rebels likely fired a surface-to-air missile that shot down the plane.

Both the government in Ukraine and the pro-Russia separatists fighting in the region denied any responsibility for downing the Boeing 777.

Russian President Vladimir Putin reportedly said Ukraine "bears responsibility" for the crash, because the plane was brought down in that country.

Sean Cronin spent most of his 20 years in the Navy flying a P3 over the Pacific looking for Russian military assets. He said he is convinced the Malaysian plane's destruction points to more than just rebel assaults.

“Politically this is a nightmare for the Russians,” Cronin said. “It is just a complete nightmare because this is coming back on them. This is their weapon, this is their technology. ... It took their training to run this equipment.”

Cronin called the attack tragic -- and planned. He said he won't believe any explanation about rebels or separatists using stolen weapons or one-man missile launchers.

“Well, I'm telling you, it wasn't a shoulder launcher. It couldn't reach that altitude,” Cronin said. “These weapons are generally limited to 5,000 feet, some of them to 10,000. Nothing that's shoulder-launched is going to track an airliner that's going 400-plus mph at 32,000 feet. It just doesn't happen.”

Members of Congress who represent the Jacksonville area shared their thoughts with News4Jax on Friday.

“Somebody with high technology fired this missile to shoot down this plane,” said Rep. Ander Crewnshaw, R-Jacksonville. “So when you do that … that's not just a war against Ukraine, not just against Europe, this is a war against the world.”

Crenshaw voiced his concern, calling it "a terrible, horrific situation."

He said Putin has to be held to a higher standard and said sanctions by the U.S. may not be enough.

"We have some sanctions against Russia. They're helpful, but they're not solving the problem,” Crenshaw said. “We've got to get to the bottom of this, and make sure that we're part of the solution. To say, 'This is against international law.' It's a war against the world, and it has to stop.”

Cronin echoed that sentiment.

“This is Russia flexing muscles to gain territory through military action,” Cronin said. “And it requires a world response.”

Rep. Corrine Brown, D-Jacksonville, issued a statement Friday that concurred with the president and Crenshaw.

In part, the statement said, “It is critical that independent, international experts are able to fully investigate the plane crash to determine who is responsible for this incident. It is incumbent upon the international community to find out who is behind this horrific act and ensure that they are brought to justice. This is a true moment that the international community needs to come together, and it is of extreme importance that they work through this to ensure this incident does not repeat itself."