EDIT: Ordered* Sorry about the title, think i caught a little brain damage mid way through.
http://www.bbc.co.uk/news/uk-england-london-29331457
She is alleged to have bought the poison from a site on the secretive online world known as the dark web, which allows users to be anonymous.
She paid for it using the virtual currency bitcoin and it was delivered in a wax candle, the court was told.
The graphic designer put the poison in the bottle and watched as her mother, who sits on the bench at Thames Magistrates' Court, drank it at her home in Stratford, east London, but nothing happened.
The bombshell in the article, if true, is:
Unknown to Ms Patel, the website she bought the poison through was under surveillance by the FBI, who tracked the sale to London, and alerted British counter terrorism police.
This doesn't make much sense. If the FBI were "monitoring" a market and were able to determine (1) that abrin was ordered, and (2) the address it was delivered to, then why didn't they do the raid BEFORE or WHEN the poison was delivered? Did they want to get more serious charges against her before making the arrest, and were therefore waiting for dear mum to die? They did manufacture a completely artificial and imaginary murder plot for DPR to be complicit in, but maybe they decided they need a body for a real solid case. Or it's possible they really were "monitoring" (more like "operating" I bet) the site and filled the order with fake poison.
If it was a real order/delivery, and really detected by "monitoring" the traffic, how did they get the address? I guess something like 50%+ of people don't use PGP, so that's plausible.
I think it's more likely they found out about this through some other means besides "monitoring" a market as poison is getting delivered. For example, monitoring non-encrypted communications from her computer/phone (she did have a terrorist-sounding last name after all (oh lighten up francis)) and she mentioned it or Googled about it.