I know what you're thinking...
Good guess, but you'd be wrong:
Well, a certain Dr. Hollister was working on developing a suspended animation formula.
After talking about in on a local talk show, vile gangster Keech decides he wants the formula for himself, even though it hasn't been tested on humans yet. It's a good way to hide out from the FBI, and when he wakes up in 100 years, his stolen loot (including a Rembrandt!) will be less hot, more valuable, and easier to fence!
Fortunately, Flash is on hand to help out...
And about 3 seconds after rousting the bad guys...
But apparently, everyone had tickets for Star Wars or something, because even the JLA can't wait to bury Barry:
Our lessons: when you find a super-hero sleeping on a park bench covered with newspapers proclaiming his death, A) The paper is probably wrong, B) The guy on the bench probably isn't the hero, and C) Make damned sure your hero is actually dead before you have a funeral.
SPOILER ALERT: Barry wan't dead, he was just in suspended animation. Who would have thought?
From Flash #199 (1970)