A woman watches rescue operations after a bus and a truck crashed on the road that links the Honduran capital with the south of the country, near Germania, 11 km south of Tegucigalpa on February 5, 2017. At least 12 people were killed and 35 injured of some 70 who were on board the bus. (Photo by Orlando Sierra/AFP Photo)

In this handout image provided by the Police of Swiss canton Valais the wreckage of a bus is seen after it crashed inside a motorway tunnel on March 13, 2012 in Sierre, Switzerland. 28 people, including 22 children, returning from a skiing holiday died in this bus accident. (Photo by Police Cantonale Valaisanne via Getty Images)

Stagecoach tests the amphibious bus, on the River Clyde on February 9, 2010 in Glasgow, Scotland. The Ј700,000 Dutch made amfibus could eventually replace the existing ferry service which is being scraped in March due to costs. (Photo by Jeff J Mitchell/Getty Images)

Swiss rescue workers wheel a wounded person on a stretcher after two regional trains crashed head on near Granges-Pres-Marnand near Payerne in western Switzerland July 29, 2013. The two trains collided in the Swiss canton of Vaud on Monday evening, injuring about 40 people, four seriously, Swiss news agency ATS reported. There was no immediate report of any deaths in the crash. (Photo by Denis Balibouse/Reuters)

This aerial picture taken on June 6, 2016, shows the scene of a collision between a freight train and a passengers train on their way between Liege and Namur, in Saint-Georges-sur-Meuse, Eastern Belgium. Investigators worked through the wreckage of a high speed train crash in eastern Belgium on Monday that killed at least three people and injured nine others. A fast-moving passenger train late Sunday slammed violently into the back of a slow-moving freight train that was travelling on the same track for reasons that remain unexplained. (Photo by Laurie Dieffembacq/AFP Photo)

An Egyptian army soldier stands guard near debris from a Russian airliner which crashed at the Hassana area in Arish city, north Egypt, November 1, 2015. Russia has grounded Airbus A321 jets flown by the Kogalymavia airline, Interfax news agency reported on Sunday, after one of its fleet crashed in Egypt's Sinai Peninsula, killing all 224 people on board. (Photo by Mohamed Abd El Ghany/Reuters)

Sheriffs' deputies look at wreckage from the crash of Virgin Galactic's SpaceShipTwo near Cantil, California November 2, 2014. A suborbital passenger spaceship being developed by Richard Branson's Virgin Galactic company crashed during a test flight on Friday at the Mojave Air and Space Port in California, killing one crew member and seriously injuring the other, officials said. (Photo by David McNew/Reuters)