Unknown apple IDs

Today I plugged my iphone 5 into my mac desktop synced it up, removed some music from my phone because i was running out of space, and then started my software update for my phone. I was given an error that required me to do a total reset of my phone. I went ahead and did the reset using the last backup i had done, set up the wifi, my icloud account with MY apple id and password, accepted terms, chose the back up, and then it asked me the following:

"Enter the apple id password for (an unknown apple id) to use for store purchases (including the app store, itunes store, and ibook store)." - i skipped the step and it asked me again with another unknown apple id, skipped that and it asked me again for another unknown id...

Both my phone and mac were purchased directly from the apple store.

I had noticed my phone acting strange recently (battery dying really fast even after all apps closed out, powered off and back on & my IT at work said they got over 400 red flags on their system from my phone when it was connected to their wifi a week ago and i wasn't using the phone)

How did these unknown IDs end up on my phone and does that mean someone may be accessing my stuff?