The strikes were announced shortly after President Donald Trump told reporters in the Oval Office that "you're going to find out" if the U.S. will respond.
The U.S. military said Wednesday it struck five alleged drug-smuggling boats over two days, killing a total of eight people while others jumped overboard and may have survived.
The US military conducted a strike against an alleged drug-trafficking vessel in the eastern Pacific Ocean, killing two people, according to US Southern Command.
President Donald Trump has indicated that the U.S. has "hit" a dock facility along a shore as he wages a pressure campaign on Venezuela, but the U.S. offered few details.
The strikes are in retaliation for the deaths of three Americans in Palmyra, Syria, on Saturday.
Hegseth said he won't release the full unedited version of video showing a Sept. 2 attack on a suspected drug boat that killed 11 people.