Virginia's governor has pledged to review authorities' handling of shootings at Virginia Tech university that left 32 people dead.
Tim Kaine's comments came amid claims by survivors that the US university did not do enough to protect students during Monday's shooting rampage.
Police said Cho Seung-hui, a student originally from South Korea, killed 30 people, before committing suicide.
He is also believed to have killed two students earlier in the day.
On Tuesday, US President George W Bush addressed a memorial service for the victims of the shootings in Blacksburg.
Mr Bush said it was "a day of sadness for our entire nation".
Speaking at a news briefing, Gov Kaine said an independent panel would carry out a "thorough" review of the authorities' handling of the disaster.
He said the panel would be appointed at the request of the university and would begin its inquiry immediately.
Gov Kaine warned against making snap judgements, saying he had "nothing but loathing" for those who took the tragedy and "make it their political hobby horse to ride".
Monday's shootings occurred in two separate locations, two hours apart.
The first took place at 0715 (1215 GMT), at West Ambler Johnston Hall dormitory, where a man and a woman were shot dead.
Then, at about 0915 (1415 GMT), 30 people were killed in the second shooting at Norris Hall, about half a mile (800 metres) away, on the same campus.
Some students complained angrily that they had received no warning from the university until an e-mail more than two hours after the first incident.
They also said that the university should have locked down the campus immediately after the shooting at the dormitory.
Student Billy Bason, 18, said: "I think the university has blood on their hands because of their lack of action after the first incident."
University officials defended their handling of the incidents, saying they acted on what they knew at the time.
"We had no reason to suspect any other incident was going to occur," Virginia Tech President Charles Steger said.
Police said they thought the first incident was isolated and "domestic" and that the gunman had left the campus.
Police later said 23-year-old Cho Seung-hui was a South Korean living legally in the US with his parents since he was eight.
Cho was studying English and had been living on the university campus.
Police have not suggested a motive for the attack.
It is understood that one of the first people to be shot was Cho's former girlfriend, the BBC's Justin Webb in Blacksburg says.
Police also say they found a disturbing note in his room in which said "You forced me to do this", our correspondent says.
But police say they have no evidence that Cho left a suicide note.
US media reported that he had been referred for counselling after producing "troubled" work in his creative writing class.
Cho was described by those who knew him as aloof from fellow students.
Larry Hincker, associate vice president for university relations at Virginia Tech, said: "He was a loner, and we're having difficulty finding information about him."
Police said two handguns - 9mm and .22 calibre weapons - were recovered at the scene of the second shooting, and that one of them was also used in the first incident.
However, they are investigating whether he had an accomplice.
'Time of anguish'
On Tuesday, President Bush attended the memorial service in Blacksburg with his wife Laura.
He called for people to offer help to bereaved relatives, and said: "In this time of anguish, I hope you know that people all over this country are thinking about you and asking God to provide comfort for all who have been affected."
Later on Tuesday evening, thousands of people, students and Blacksburg residents, young and old, gathered on the campus drill field - usually the scene of football games - for a candlelit vigil.
Volunteers handed out the candles, held in cups to protect them from the wind, and all donated by people and businesses in the town over the past 24 hours.
As darkness fell, everyone raised their candles for a long moment's silence before breaking into choruses of the university's "Let's go Hokies" chant.
It was a very moving symbol of the town's unity, with many people saying they believed the "Hokie family" would come out all the stronger in the face of adversity, says BBC correspondent Laura Smith-Spark.