Some of the emails had the subject line, "Think Twice." They were sent from a spoofed email address. The sender claimed to have had an associate plant a small bomb in the recipient's building and said the only way to stop him from setting it off was by making an online payment of $20,000 in bitcoin.
Authorities would go on to undo the email's spoofing, and uncover the person that sent the emails. 
( z1 go-on :ARG1 ( z2 and :op ( z3 undo :ARG0 ( z4 authority ) :ARG1 ( z5 spoof :ARG1 ( z6 email ) ) ) :op ( z7 uncover :ARG0 z4 :ARG1 ( z8 person :ARG0-of ( z9 send :ARG1 z6 ) ) ) ) )