SeaTac Tower: Nobody Home

Sorry if this has been mentioned before, but I just saw a story on my local
news (in the Pacific Northwest) about an incident at SeaTac airport on April
11th, and this is the first I've heard of it.

Apparently, there was a period of about 30 minutes on that day (no mention
as to what time of day) when no incoming flights could get a response from
the tower. The security guard at the tower was eventually asked to
investigate, and it seems that the lone controller on duty had fallen
asleep. The story ended by noting that the FAA now required two controllers
on duty in the SeaTac tower at all times.

Anybody else hear of this? I'm guessing that it couldn't have been during a
busy time, as that would have caused utter chaos. I'm also guessing that
this sort of thing isn't unprecedented.