The man said he would kill everybody before using a bomb witnesses say.
A man at the Ocean beach Library threatened to bomb the branch, but not before killing everyone inside reports ABC 10.
It happened on Monday afternoon after the man asked people for loose change.
"A man started bugging people for a quarter," said security guard Jesus McClaskey. "Nobody has any money so he started screaming and yelling at everybody."
The guard then goes on to say that the man became volatile and screamed at library patrons and their children before he was escorted outside.
"He said he's going to kill people," McClaskey said. "Kicking the door real bad."
The staff and others barricaded the door so the irate man could not get back inside.
Video of the event shows the man screaming, and attacking the building.
McClaskey adds, "And he said 'This place is going to be bombed, but before I bomb it everybody is going to be dead.'"
Library manager Matthew Beatty said this is the worst incident of its kind he’s witnessed.
"I was really bothered because we had families in the library, we get lots of small kids here," Beatty said. "That was the loudest incident we've had since I've been here and I've been here a dozen years."
The man has been permanently restricted from using the library.
You can watch the ABC 10 News report HERE.