Throughout history, April has borne witness to many tragedies. The following is a look back on some of those major events:
April 14, 1865 - President Abraham Lincoln is assassinated at Ford's Theatre in Washington, DC.
April 15, 1912 - The Titanic sank in the North Atlantic Ocean.
April 4, 1968 - Martin Luther King, Jr. was assassinated in Memphis, Tenn.
April 26, 1986 - Chernobyl nuclear disaster occurred in the Ukraine.
April 26, 1991 - Andover, Kansas Tornado, a violent outbreak of tornadoes which left 24 people dead and hundreds injured.
April 19, 1993 - FBI's siege of Waco Compound ended violently after a 51-day standoff. Seventy-five perished either by gunshot or by fire inside the compound. Twenty-five of the dead were children.
April 19, 1995 - The Oklahoma City bombing was a terrorist bomb attack on the Alfred P. Murrah Federal Building in downtown Oklahoma City. The Oklahoma blast claimed 168 lives, including 19 children under the age of 6, and injured more than 680 people.
April 20, 1999 - The Columbine High School massacre was a school shooting that took the lives of 12 students and one teacher. Twenty-one additional students, with three other people were injured.
April 16, 2007 - The Virginia Tech massacre was a school shooting that took place on the campus of Virginia Polytechnic Institute and State University in Blacksburg, Va. Thirty-two people were shot and killed and 17 were wounded in two separate attacks.
April 15, 2013 - Two bombs exploded during the Boston Marathon at approximately 2:50 p.m. EDT on Boylston Street near Copley Square, just before the finish line. The blasts killed 3 people, and injured at least 176 others.
April 17, 2013 - An exlosion occurred at the West Fertilizer Companyplant in West, Texas. Early media reports indicate heavy casualties. The cause of the blast is currently unknown.