Dzhokhar and Tamerlan Tsarnaev set off two pressure cooker bombs during the running of the Boston Marathon, killing three people and injuring 264 others.
At a GATT ministerial meeting in Marrakesh, Morocco, representatives of 123 countries and the European Communities signed an agreement to establish the World Trade Organization.
The Hillsborough disaster, a human crush that caused 97 deaths in the worst disaster in British sporting history, occurred during an FA Cup match between Liverpool and Nottingham Forest in Sheffield.
American restaurateur Ray Kroc opened the ninth McDonald's franchise in Des Plaines, Illinois, an occasion considered to be the founding of the present corporation.