Update 2 pm: "The barrage likely originated with a large amount of poorly secured devices like internet-connected cameras, [Internet] routers, and digital video recorders, according to an analysis of the attack on [cybersecurity tracker Brian] Krebs's site," notes Bloomberg's Nate Lanxon and colleagues  here.  More from Dyn, the hosting company and an apparent key target of the attack, here.

"These devices, collectively referred to as the 'Internet of Things,' have been the source of an increasing number of attacks since early 2015, Flashpoint and Level 3 Threat Research Labs said in a report published last month," Bloomberg added.  -- More via Forbes, channeling Flashpoint. -- News site NJ.com has been down much of the day. Paypal jammed.

Earlier: "Criminals this morning massively attacked Dyn, a company that provides core Internet services for Twitter, SoundCloud, Spotify, Reddit and a host of other sites, causing outages and slowness for many of Dyn's customers," writes KrebsOnSecurity here.

More on the early stage of the attack in USAToday here. Updated after 3 pm here. -- This is a larger-scale DDoS (distributed denial-of-service) attack and "may be the beginning of a bleak future," writes William Turton at Gizmodo here.

Twitter and Netflix sites appear down from my workstation in Philly (noon Friday).  So does Dyn, which had earlier posted warnings about the attack. -- Twitter back up before 1.