There’s much yet to be discovered as I understand there are still some fires in the buildings. This is not going to play out well no matter what is discovered. But someone provided this stuff for these bombs and someone got this guy they’ve arrested to pull it off. There are “others” who have likely gone into hiding somewhere as well.
Yeah, this is too ‘big’ for this guy to be a ‘loner’. It was well coordinated. JMHO.