Updated

Virginia Tech shooter Cho Seung-Hui's homage to the Columbine High School killers has made preparations for Friday's eighth anniversary of the Colorado rampage all the more devastating, survivors and victims' relatives said.

In the video he mailed to NBC during a gap in Monday's fatal shootings of 32 people at Virginia Tech, Cho, 23, referred to "martyrs like Eric and Dylan" in a disjointed attempt to explain his motives for killing the others and himself.

The decision by NBC and other networks to air the footage drew immediate criticism from relatives of the Virginia Tech victims, but Columbine families said Cho's acknowledgment of high school shooters Eric Harris and Dylan Klebold has made the anniversary all the more raw.

"I felt like I was looking at Lauren's murderer. It's as if someone has been cruelly replaying April 20," said Dawn Anna, whose 18-year-old daughter, Lauren, was among 12 Columbine students slain along with a teacher by classmates Klebold and Harris, who took their own lives.

Columbine High will be closed Friday, as it has been every April 20 since the 1999 shootings.

Invoking the Columbine tragedy, Gov. Bill Ritter asked state residents to join a bell-ringing and moment of silence taking place across the country for the Virginia Tech victims Friday.

"We experienced a terrible tragedy at Columbine High School," Ritter said. "The people of Colorado will stand in solemn silence on the anniversary of that dreadful day with the people of Virginia as they grieve."