Virginia Tech Massacre. Why weren't students notified?

Back from being way all day and far from the Internet, I just learned about the horrific killings at Virginia Tech.  How terrified the students must have been.  How awful for the victims' families.  I can't imagine the shock their parents must feel after thinking their children were safe at college.  I can't imagine the shock and pain their friends and fellow students are going through.   

I join everyone in sorrow at this tragedy and in prayers for those touched by the shootings.

32 killed!  I don't understand the 2 hour lag between the first murder and the classroom murders. 

How  a heavily armed man could walk around campus without people noticing and calling security is beyond me. 

Why after bomb scares last week and a double murder at about 7:15, did it take 2 hours for school officials to warn students to "be cautious".

Two people killed and the gunman at large seems to me to warrant more than a "be cautious."    What was campus security doing?

We've seen Columbine.  We've been horrified at the Bestlan massacre.  Now we're seeing Virginia Tech.

How many more?

In an emergency being connected is more important than ever.  Why wasn't there an emergency communications plan for all  the students? The elements are all in place.  All students have phones and computers.  Why weren't all the students on a email, phone text message alert?

Any plan could have saved lives.