Memorial services are to be held in Oklahoma City and McAlester on Monday to remember the 168 victims of the April 19, 1995, bombing of the Alfred P. Murrah Federal Building.
Survivors and victims' relatives are to gather at the Oklahoma City National Memorial at 9:02 a.m. - the moment the bomb detonated. Plans included reading the names of the victims and observing 168 seconds of silence, one second for each of those who died.
Survivors and members of victims' families attending Nichols' trial in McAlester planned a private observance at noon at the First Baptist Church, located behind the courthouse.
Meanwhile, an FBI agent who interrogated Nichols two days after the deadly bombing was scheduled to be questioned by Nichols' defense attorneys as testimony in his state trial in McAlester moved into a fifth week.
Nichols, 49, is serving a life sentence on federal convictions for his role in the bombing. He was convicted of conspiracy and involuntary manslaughter for the deaths of eight federal law enforcement officers.
Nichols is on trial for 161 counts of first-degree murder for the deaths of the other 160 victims and one victim's fetus. Prosecutors are seeking the death penalty.
On Friday, FBI agent Steve Smith testified that he and other FBI agents interrogated Nichols for nine hours on April 21, 1995, two days after the bombing.
Nichols told investigators three times that he did not have bomb-making materials in his house in Herington, Kan., Smith said.
During the search, investigators found detonation cord and other explosives they said were similar to components used in the bombing.
Nichols was at home the day the bomb exploded. But prosecutors allege he helped executed bomber Timothy McVeigh build the homemade 4,000-pound ammonium-nitrate-and-fuel-oil bomb and pack it inside a Ryder truck the day before.
By Tim Talley