Gotta set the dragnet. Not a lone wolf.
I agree. Better to haul in the most possible involved people and get all info possible from them, rather than immediately naming just the one arrested.
Indeed.
From CNN:
Authorities are investigating additional similar packages mailed to addresses in Texas that may be connected to the same sender in Canada, CNN previously reported, according to a US law enforcement official.
https://www.cnn.com/2020/09/20/politics/poison-ricin-addressed-trump-arrest/index.html
No nationality offered either.
Also not only sent to the WH, but to other federal facilities, including in Texas.