In the wake of the bombing of the Malaysian Airlines Flight MH17 in Ukraine, a lot of questions are being raised about who is to be blamed for the attack and why civilian planes have become targets of such military or rebel attacks over the years.
Many, like the infamous 9/11, have also turned out to be terror strikes.
While Some may have been genuine cases of mistaken identity, in others, the aircraft may have violated wartime airspace restrictions.
In this case, however, it is too early to speculate, given the political tensions between Ukraine and Russia, and the fact that the crash site is so close to the Russian border.
While investigators and intelligence agencies try to figure out the intricacies of the attack, letâ€™s have a look at the top ten most controversial commercial plane bombings/crashes over the years.
Siberian Airlines Flight 1812
The MH17 is not the first case involving the Ukrainian military. Siberia Airlines Flight 1812 crashed over the Black Sea way back on 4 October 2001, en route from Tel Aviv, Israel to Novosibirsk, Russia, killing all 78 aboard.
The Russian ground control centre in Sochi suddenly lost contact with the airliner. Soon afterwards, the pilot of an Armenian plane crossing the sea nearby reported seeing the Russian plane explode before it crashed into the sea.
Occurring less than a month after the September 11, 2001 attacks, the crash was initially thought to be an act of terrorism.
Ukraine did not initially claim responsibility, but later admitted its military accidentally shot the plane down with a surface-to-air missile from the Crimean peninsula during a military exercise. On the day of the shoot-down, the Ukrainian military was conducting a massive military exercise which involved shooting 23 missiles at drones.
Pan Am Flight 103
Who can forget the tragic mid air rupture of Pan Amâ€™s flight no 103 in the Scottish town of Lockerbie in 1988 just before Christmas on December 21? All 243 passengers and 16 crew on board died in the incident, along with 11 people on the ground.
Soon after the plane took off and attained a height 31,000 feet, a bomb detonated near the left wing. Power went out instantly and the plane began breaking apart.
A suitcase bomb aboard New York-bound Pan Am Flight 103 was concluded to be the reason of the mid air blast.
Only one suspect, a Libyan intelligence agent, was ever convicted in connection with the attack. However, in 2003, Libyan leader Muammar Gaddafi accepted responsibility for the Lockerbie bombing and paid compensation to the families of the victims, although he maintained that he had never given the order for the attack.
Air India Flight 182
On 23 June 1985, Boeing 747-237B was blown up by a bomb at an altitude of 31,000 feet and crashed into the Atlantic Ocean while in Irish airspace.
A total of 329 people were killed, including 268 Canadians, 27 British citizens and 24 Indians.
The bombing of Air India 182 occurred at the same time as the Narita Airport bombing. Investigators believe that the two plots were linked, and that the group responsible was aiming for a double-bombing.
However the bomb at Narita exploded before it could be loaded onto the plane. Canadian law enforcement determined that the main suspects in the bombing were members of the Sikh militant group, Babbar Khalsa.
The attack is thought to have been a retaliation against India for the operation carried out by the Indian Army Operation Blue Star.
Though a handful of members were arrested and tried, Inderjit Singh Reyat, a Canadian national, remains the only person legally convicted of involvement in the bombing. Singh pleaded guilty in 2003 to manslaughter.
He was sentenced to 15 years in prison for building the bombs that exploded aboard Flight 182 and at Narita.
Itavia Flight 870
On 27 June 1980, around forty minutes after take-off from Bologna, Italy, an unknown object was seen approaching the Itavia Flight 870 aircraft and soon after, the plane disappeared from radar screens.
All 81 on board were killed and parts of the wreckage were found floating on the water. The cause of the crash was declared unknown, but one of the leading theories was that it was shot down by NATO forces or jet fighters.
This theory was supported by the then Italian Prime Minister Francesco Cossiga, who attributed the downing to French interceptors, later covered as a part of the Gladio clandestine operation by NATO.
On 23 January 2013 Italyâ€™s top criminal court ruled that there was "abundantly" clear evidence that the flight was brought down by a missile.
Iran Air Flight 655
In a tense time in a volatile region, the USS Vincennes was sailing the Persian Gulf in 1988 to help keep the key oil shipping lane open and to monitor the war between Iran and Iraq.
Iran Air Flight 655 a commercial flight operated by Iran Air on July 3, 1988, was shot down by the US Navy Ticonderoga-class guided missile cruiser, which fired a SM-2MR surface-to-air missile.
The airplane was destroyed between Bandar Abbas and Dubai, killing all 290 passengers and crew.
It was later claimed by United States Government that USS Vincennes was in Iranian waters at the time of the attack, and IR655, an Airbus A300, was mistaken for an Iranian F-14 fighter jet plane.
Under an agreement in 1996 at the International Court of Justice, US agreed to pay Iran $61.8 million in damages for the accident.
Korean Air Lines Flight 007
Also known as "The Soviet killing of a sitting US Congressman", Korean Air Lines Flight 007 was shot down by a Soviet fighter plane on September 1, 1983, killing all 269 passengers and crew, including Larry McDonald, a Congressman from Georgia then in his fourth term.
The United States government reacted with horror to the disaster. The Department of State suggested that the Soviets knew the plane was an unarmed civilian passenger aircraft. President Ronald Reagan called the incident a "massacre".
Despite the heated public rhetoric, many Soviets and American officials and analysts privately agreed that the incident was simply a tragic misunderstanding.
El Al Flight 402
Israeli jet El Al Flight 402, an international passenger flight, was flying from Vienna, Austria, to Tel Aviv, Israel via Istanbul on July 27,1955 when it strayed into Bulgarian airspace.
The plane was shot down by two Bulgarian MiG-15 jet fighters and crashed near Petrich, Bulgaria, killing all 51 passengers and seven crew aboard.
The shootdown of the Lockheed L-049 Constellation four-engine propliner happened during a time of strained relations in the Cold War between the Eastern Bloc and the West.
Eight years after the attack, Bulgaria agreed to pay a total of $195,000 ($1.5 million in current dollars) to Israel, having already compensated non-Israeli passengers.
Cathay Pacific Airways
On July 23, 1954, mainland China's People's Liberation Army fighters shot down a Cathay Pacific Airways (the airline of Hong Kong, then under British control) C-54 Skymaster flying from Bangkok to Hong Kong; 10 out of the 19 passengers and crew died.
In apologizing for the attack to Britain days later, the Chinese government stated that they had thought the plane was a military aircraft from the Republic of China n (Taiwan) on an attack mission against Hainan Island (near where the shoot-down took place).
Libyan Arab Airlines Flight 114
On February 21, 1973, a Libyan Arab Airlines 727 flying from Tripoli to Cairo got lost and flew over the Sinai peninsula, which had been under Israeli control since the Six-Day War in 1967.
After giving signals to land and firing warning shots, Israeli jets shot down the plane, killing 108 of the 113 people on board, and leaving four passengers and a co-pilot alive.
David Elazar, the chief of staff of the Israeli armed forces, took responsibility for ordering the shoot-down.
Defense Minister Moshe Dayan called the event an "error of judgment" and the Israeli government compensated the families of victims. Libya condemned the attack as "a criminal act" while the Soviets called it a "monstrous new crime."
And the bombing that changed the face of terrorism world over and defined a new world order in global politics, was the twin crash of the World Trade Centre towers in Manhattan, New York, better known as the 9/11 attack.
Defying all prior norms of bombing a hijack like never seen before four passenger airliners were hijacked by 19 al-Qaeda terrorists so they could be flown into buildings in suicide attacks.
Two of those planes, American Airlines Flight 11 and United Airlines Flight 175, were crashed into the North and South towers, respectively, of the World Trade Center complex.
A third plane, American Airlines Flight 77, was crashed into the Pentagon leading to a partial collapse in its western side.
The fourth plane, United Airlines Flight 93, was targeted at Washington, DC,but crashed into a field near Shanksville, Pennsylvania, after its passengers tried to overcome the hijackers.
In total, almost 3,000 people died in the attacks, including the 227 civilians and 19 hijackers aboard the four planes.
Planned and executed by Al Qaeda under the guidance of Osama Bin laden this attack altered east-west relations in a major way for the coming years, till today.