SEOUL: As South Koreans observe a seven-day mourning period for the 179 victims, including passengers and crew, of the Jeju Air Flight 2216 crash, authorities are looking into the probable reasons behind the fiery crash which was only survived by two flight attendants. The plane was carrying 181 people from Thailand to South Korea when it made a mayday call and belly-landing before crashing into a barrier and bursting into flames. Here's an overview of what we know about the deadliest plane crash on South Korean soil. A Boeing 737-800 aircraft belonging to low-cost carrier Jeju Air, flying from Bangkok to Muan airport, was warned of a bird strike by the control tower, officials said, during its first attempt at landing shortly after 9:00am. Minutes later, the pilot issued a "mayday" warning and tried to land again. Video showed the plane, its landing gear still retracted, attempting a belly landing. Dramatic video shows the plane skidding along the runway with smoke trailing behind until it slams into a wall at the end and bursts into flames. All 175 passengers and four of the six crew members onboard were killed. The passengers, aged three to 78, were all Korean apart from two Thais, authorities said. Rescue workers plucked two survivors — flight attendants aged 25 and 33 — from the wreckage. Investigations have been launched, but officials are focusing on a possible bird strike and poor weather. "It really has to be a series of catastrophic events that led to such a high loss of life," aviation consultant Philip Butterworth-Hayes told . "Crash protection systems on board are extremely robust," he said, describing the disaster as "the most serious incident I've seen" in recent years. When asked whether the runway might be too short, one official said this was likely not a factor. "The runway is 2,800 metres long," or 9,200 feet, "and similar-sized aircraft have been operating on it without issues," the official said. Both black boxes — the flight data recorder and the cockpit voice recorder — have been recovered, said Deputy Transport Minister Joo Jong-wan. A bird strike — a collision between a bird and an aircraft in flight — can be hazardous to aircraft. Jets can lose power if birds are sucked into their air intakes, according to the International Civil Aviation Organisation (ICAO), a UN agency. Bird strikes have caused a number of fatal accidents globally. "We're looking at substantial birds hitting an engine, and that is, as we know, very rare," said Butterworth-Hayes. He mentioned the famous "Miracle on the Hudson" incident in 2009, when a US Airways Airbus A320 was forced to ditch in New York's Hudson River after a bird strike damaged both of its engines. All aboard managed to escape. Hundreds of firefighters and other emergency responders, including military, were deployed to the Muan airport area, with the country's acting president designating the site a special disaster zone. Family members, many crying in despair, waited on the airport's first floor. The accident occurred with South Korea in the throes of a political crisis that began when then-president Yoon Suk Yeol declared martial law on December 3, days before being impeached. Acting President Choi Sang-mok, on his third day in office, convened an emergency meeting with cabinet members Sunday and visited the crash scene. South Korea's aviation industry has a solid safety record and the crash was the first fatal accident for Jeju Air. On August 12, 2007, strong winds caused a Jeju Air-operated Bombardier Q400 carrying 74 passengers to veer off the runway at another southern airport, Busan-Gimhae. A dozen people were injured. Before Sunday, the deadliest plane crash on South Korean soil took place on April 15, 2002, when an Air China Boeing 767 travelling from Beijing hit a hill near Busan-Gimhae, resulting in 129 deaths. The most recent fatal crash of a South Korean airline happened in San Francisco, California on July 6, 2013. Asiana Airlines' Boeing 777 aircraft missed its landing, leaving three dead and 182 hurt. The deadliest disaster to hit a South Korean airline goes back to September 1, 1983, when a Soviet fighter jet shot down a Boeing 747, which Moscow claimed was mistaken for a spy plane. All 23 crew and 246 passengers aboard the Korean Air flight —a New York-to-Seoul flight via Anchorage, Alaska — were killed.