25th anniversary of Oklahoma City bombing The north side of the Albert P. Murrah Federal Building in Oklahoma City shows the devastation caused by a fuel and fertilizer truck bomb that was detonated, killing 168 people. (BOB DAEMMRICH/AFP via Getty Images)
25th anniversary of Oklahoma City bombing Protective covering is draped over the Alfred P. Murrah Federal Building in Oklahoma City after a terrorist bomb killed 168 people. (J. Pat Carter/Getty Images)
25th anniversary of Oklahoma City bombing Rescue crews and agents from several federal agencies stand in front of the remains of the Alfred P. Murrah after the bombing 25 years ago. (ROBERTO SCHMIDT/AFP via Getty Images)
25th anniversary of Oklahoma City bombing. A rescue crew searches for bodies April 20. 1995, at the Alfred P. Murrah Federal building in Oklahoma City. (POOL/AFP via Getty Images)
25th anniversary of Oklahoma City bombing Rescue workers climb over debris after a bomb exploded at the Albert P. Murrah Federal Building in Oklahoma City on April 19, 1995. (AFP/AFP via Getty Images)
225th anniversary of Oklahoma City bombing Frightened civilians react to the terrorist bombing at the Alfred P. Murrah Federal Building in Oklahoma City, April 19, 1995. (J. Pat Carter/Getty Images)
25th anniversary of Oklahoma City bombing Timothy McVeigh sits for an interview with Rob Night, left, and Stephen Jones while in prison June 23, 1995, in Oklahoma City. McVeigh would be convicted in the bombing that killed 168 people. (Pool/Getty Images)
25th anniversary of Oklahoma City bombing Timothy McVeigh, center, is led from the Noble County Courthouse in Perry, Oklahoma, by FBI agents after being charged in the April 19, 1995 bombing of the Alfred P. Murrah Federal Building in Oklahoma City. (BOB DAEMMRICH/AFP via Getty Images)
Terry Nichols Mug Shot Terry Nichols was convicted of being an accomplice to Timothy McVeigh in the Oklahoma City bombing of the Alfred P. Murrah Federal Building in April 1995. (Donaldson Collection/Getty Images)
Los Angeles Firefighters Greg Gonzalez(L) and Trac OKLAHOMA CITY, OK - APRIL 25: Los Angeles Firefighters Greg Gonzalez(L) and Tracie Gallagher(R) rest with their dogs 24 April at the site of the 19 April bomb attack on the Oklahoma federal building, as rescue efforts to find any survivors continue. The official death toll in the attack rose to 79, authorities said 24 April. AFP PHOTO (Photo credit should read POO/AFP via Getty Images) (POOL/AFP via Getty Images)
25th anniversary of Oklahoma City bombing Oklahoma City terrorist bombing victim Brandon Denny, 4, had to celebrate his birthday from a hospital bed, as his parents, Jim and Claudia Denny, hold up his birthday cupcake lit up with two candles. (Taro Yamasaki/The LIFE Images Collection via G)
25th anniversary of Oklahoma City bombing President Clinton discusses search and rescue details with Oklahoma Gov. Frank Keating as Keating's wife Cathy, Lt. Gov. Mary Fallin, and emergency workers look on April 24, 1995 in Oklahoma City. (Diana Walker/Getty Images)
Oklahoma City Oklahoma OKC City downtown Memorial Wall with messages at bombing site on April 1995 A downtown Memorial Wall in Oklahoma City had messages written to commemorate the bombing. (Bill Bachmann/Universal Images Group via Getty)
25th anniversary of Oklahoma City bombing Families and friends of victims gathered at the Oklahoma City National Memorial dedication ceremonies April 19, 2000. (Cynthia Johnson/Getty Images)
Oklahoma City bombing anniversary The Oklahoma City Bombing Memorial commemorates the terrorist attack that happened April 19, 1995. (Bill Bachmann/Universal Images Group via Getty)
Oklahoma City bombing anniversary/ Writing on the walll at the Oklahoma City Bombing Memorial. (Bill Bachmann/Universal Images Group via Getty)
25th anniversary of Oklahoma City bombing The Oklahoma City National Memorial has 168 bronze-dipped chairs to commemorate the people who died during the bombing, April 19, 1995. (Steve Liss/The LIFE Images Collection via Getty Images)
25th anniversary of Oklahoma City bombing President Bill Clinton and Doris Jones, who lost a family member in the Oklahoma City bombing, visit the victims National Memorial on April 19, 2000. (LUKE FRAZZA/AFP via Getty Images)
25th anniversary of Oklahoma City bombing Jay B. Walker visits his fraternity brother for the first time before the 2016 memorial service for the Oklahoma City bombing victims. (J Pat Carter/Getty Images)
25th anniversary of Oklahoma City bombing Family members of those lost in the Oklahoma City bombing grieve as they watch the remains of the Alfred P. Murrah building demolished. (David Butow/Corbis via Getty Images)
25th anniversary of Oklahoma City bombing Mike Traynor, the uncle of 14-year-old Ashley Eckles, hugs a police officer after attending an April 24, 1995, burial service for his niece, who was killed in the Oklahoma City bombing. (TIMOTHY A. CLARY/AFP via Getty Images)
25th anniversary of Oklahoma City bombing Greg Leasure prays in front of the chair representing his sister, who was killed during the Oklahoma City terrorist bombing April 19, 1995. (ROBERTO SCHMIDT/AFP via Getty Images)
25th anniversary of Oklahoma City bombing Tina Babcock of Oklahoma City holds a teddy bear as she attends a candlelight memorial service held at the Parents Assistance Center to remember the 19 children killed in the Oklahoma City bombing. (CHRIS WILKINS/AFP via Getty Images)
25th anniversary of Oklahoma City bombing Wendy Heiser, left, and Dee Weiland read an extra edition of the Rocky Mountain News in front of the Byron G. Rogers Federal Building after hearing Timothy McVeigh had received the death penalty after his conviction. (DOUG COLLIER/AFP via Getty Images)
25th anniversary of Oklahoma City bombing The Oklahoma City Bombing Memorial is lit up at night. (Orjan F. Ellingvag/Corbis via Getty Images)
