PRO PUBLICA: “Counterterror officials believe the brothers were Islamic extremists. And the information available so far suggests that they appeared to integrate well into U.S. society, yet slid into a spiral of Islamic radicalization with bloody results. The profile has similarities to the home-grown terrorists behind attacks in Madrid in 2004 and London in 2005, according to counterterror officials.”

Related: Brothers in Marathon bombings took two paths into infamy.

Also: License Plate: Terrorista#1. And more arrests. Plus this odd detail:

Two Russian speaking men in their early 20s later arrived at the apartment and told reporters they were journalists from the Boston Globe.

They then entered the apartment through an unlocked patio door. When asked what they were doing they said: ‘We are friends of theirs. They are talking, they are talking’ and closed the door.

When MailOnline rang the City desk of the Boston Globe, a man said: ‘We’re very busy right now. Consider us informed’.

Hmm.