my yahoo account likely been hacked, broker not a contact

several days ago, a broker in title capablesalmon and other two name suffix with "salmon" chatted with me in my 3 different yahoo accounts within my digsby. it first just qustions, then finally got offensive. for i don't familiar with digsby, i don't know how to block or delete the demon from my chat window. today i checked all my 3 yahoo accounts, never found the demon in my contacts. now in my digsby contact list i yet can't find the devil.
chat history list below:
in my yahoo id fae****:
(16:10:12) squigglysalmon You seem to be leaking coolant at an alarming rate.
(16:28:37) fae**** what do u mean? i m not a native English speaker.
(18:28:38) squigglysalmon Who is squawkingsalmon? What language do you speak natively?
(18:28:35) squigglysalmon you said straight men want to be lesbians. I said not me. I am totally straight. Take my word at it. I am one of the greatest lovers known. All the ladies who've ever known the pleasure will tell you.

in my yahoo id benz****:
(16:29:36) blurrysalmon I don't believe your lies.
(16:30:35) benz**** i don't lie. never lie, except God's message i interpret only in my heart and in deep faith.
(16:31:02) benz**** that might be a bit strange in a mob's ear.
(16:34:53) blurrysalmon Yeppppp
(16:34:57) blurrysalmon I agreeee.
(16:34:59) benz**** hi
(16:35:14) blurrysalmon hello.
(16:35:33) blurrysalmon ... do I know you?
(16:36:47) benz**** what aspect would like to know me more. my profile quite detailed and transparent. my blog http://benz****.blogspot.com
(16:37:33) blurrysalmon Riiiightttt.
(16:38:20) benz**** which nation r u belongs to?
(16:38:28) blurrysalmon SAMOA
(16:41:06) benz**** what samoa stands for?
(16:42:50) benz**** bye, i will went offline.

in my yahoo id war*****:
(18:51:01) capablesalmon You have mansions in your eyes!
(18:54:02) war***** what do u mean?
(18:58:47) capablesalmon hi
(18:59:25) war***** hi,
(19:00:08) capablesalmon just to make sure
(19:00:25) capablesalmon u kno what's going on right?
(19:00:56) war***** sorry, a bit busy. talk later.