RICHMOND, Va.  During the worst campus shooting spree in American history, Virginia Tech officials locked down some administrative offices and warned their own families more than an hour and a half before the rest of the campus was alerted, according to revisions made in the state’s official report on the rampage.

The revelations come more than two and a half years after the gunman, Seung-Hui Cho, went on a rampage that killed 32 students and faculty members before taking his own life, and only 10 days before oral arguments were to begin in lawsuits challenging the university’s handling of the matter.

They do not change the original thrust of the report  that university officials could have saved lives by notifying students and faculty members earlier about the killings on campus. But they provide a more detailed picture of the mistakes made by university officials in handling the emergency. The report, for instance, indicates that students who were initially locked down at West Ambler Johnston residence hall, where the first two victims were killed, were later released from the building by the police and allowed to attend their 9 a.m. classes. Two of those students then went to class in Norris Hall, where they were killed by the gunman.

And university officials failed to contact the family of the gunman’s first victim, Emily Hilscher, until after she had died, even though Ms. Hilscher survived for three hours and was taken to two hospitals before her death.