Throw a bomb: an Attack Action or Bonus Action or either?

@ChrisPerkinsDnD On pg 267 of DMG throw a bomb is action. But is it treated like an Attack Action or Bonus Action or either?

— Salomon (@GeneralWarmonk) July 7, 2017

If something can be done as a bonus action, the text specifically calls that out. (See "Bonus Actions" on page 189 of the PH.) #WOTCstaff https://t.co/fBp1YqfMfq

— Christopher Perkins (@ChrisPerkinsDnD) July 7, 2017