BERLIN/MEXICO CITY: German Chancellor Angela Merkel and Foreign Minister Frank-Walter Steinmeier on Thursday called for an independent, international investigation into the downing of a Malaysian airliner over eastern Ukraine.

UN Secretary-General Ban Ki-moon also called for a "full and transparent international investigation” as he offered "my deep condolences to the families and loved ones of the victims and people of Malaysia.”

US President Barack Obama and Ukrainian President Petro Poroshenko agreed in a telephone call on the need to prevent tampering with debris.

Ukraine accused “terrorists” — militants fighting to unite eastern Ukraine with Russia — of shooting down the Malaysia Airlines’ Boeing 777 as it flew from Amsterdam to Kuala Lumpur with 298 people aboard.

Leaders of the rebel Donetsk People’s Republic denied any involvement and Russian President Vladmir Putin says Ukraine bears responsibility for the crash.

Of 298 people on board Flight MH17, 154 were Dutch nationals, an official from the carrier said.

Air traffic control lost contact with the Boeing 777-400 around 14:15 (12:15 GMT) near the Russian-Ukrainian border, the Malaysia Airlines official said.

Flight MH17 took off from Schiphol shortly after noon and was supposed to land in Kuala Lumpur at around 06:10 a.m. local time, Gorter said.

Malaysia Airlines will send a team to Ukraine on Friday to help with the investigation.

Merkel called for an “immediate, independent investigation into the causes of the crash,” German government spokesman Steffen Seibert said in a statement.

“For the chancellor, the suspected circumstances in which the plane was allegedly shot down from a great height are shocking,” he said.

“If this news is confirmed, she said it would represent a further tragic escalation of the conflict in eastern Ukraine,” Seibert added.

In a statement issued after he landed in Mexico City, Steinmeier had earlier said: “The separatists must immediately grant emergency and security services access to the crash site and an independent, international investigation must commence immediately.”

Who launched the missile?

US officials said there was little doubt that the plane was struck by a surface-to-air missile but it was unclear who fired the weapon.

Intelligence analysts are reviewing data from a military satellite and other sources to determine whether the missile was launched by pro-Moscow separatists in Ukraine, Russian troops across the border or Ukrainian government forces, two US officials told AFP on condition of anonymity.

“We are working through all the analysis,” said one official.

At an event in Detroit, Vice President Joe Biden said the US-made Boeing 777 was intentionally “blown out of the sky.”

The aircraft was “apparently... and I say apparently because we don’t have all the details yet... shot down. Not an accident. Blown out of the sky,” Biden said.

Finger-pointing

Shortly thereafter, Ukrainian leaders accused pro-Russian separatists of bringing down the airliner in a “terrorist” attack.

Speculation has focused on the possibility that the airliner was shot down inadvertently, possibly by pro-Russian forces believing they were targeting a Ukrainian army transport plane.

The aircraft was reportedly flying at an altitude of more than 30,000 feet (10 kilometers), putting it well within range of Russian-made Buk missiles that are in the arsenals of both Ukrainian and Russian forces.

Widely used, the Buk surface-to-air missiles are mobile systems installed on wheeled or tracked vehicles and are designed to strike aircraft, cruise missiles, helicopters and other targets.

Before the conflict in Ukraine began, Kiev government forces had about six to eight batteries of the missile, according to military analysts.

Russia has many more at its disposal, as well as more sophisticated missiles, though it remains unclear if they are deployed near Ukraine.

But Russian President Vladmir Putin says Ukraine bears responsibility for the crash.

A Kremlin statement early Friday said Putin opened a meeting with his economic advisers by calling for a moment of silence over the crash.

Then, he said, “This tragedy would not have happened if there were peace on this land, if the military actions had not been renewed in southeast Ukraine. And, certainly, the state over whose territory this occurred bears responsibility for this awful tragedy.”

US warns against removing evidence

In Washington, the White House warned that evidence from the crash site must not be moved until a “thorough and transparent” investigation has taken place.

In this phone conversation Ukraine’s president, Obama assured that US experts will “offer all possible assistance immediately” to investigate what caused the plane to plunge from the sky.

“The presidents emphasized that all evidence from the crash site must remain in place on the territory of Ukraine until international investigators are able to examine all aspects of the tragedy,” the White House said.

The statement raised the possibility that US officials are concerned pro-Russian forces could try to tamper with the evidence of the wrecked aircraft to cover up who is to blame.

US officials say they are convinced that the jet, traveling from Amsterdam to Kuala Lumpur, was hit by a surface-to-air missile.

But they have not yet been able to say who is to blame for firing the missile, and from where it was launched.

Obama also spoke by telephone to Malaysian Prime Minister Najib Razak, as his country reeled from the second disaster to strike the national airline within four months.

Malaysia Airlines flight MH270 disappeared on March 8, and is believed to have crashed into a remote part of the Indian Ocean, though no trace of the plane has yet been found.