REUTERS/Jason Reed
Late Wednesday night a Syrian base in the coastal area of Latakia - which held Russian-made surface-to-air missile systems - was destroyed.
The immediate speculation was that Israel was involved, but that wasn't certain until an unnamed White House official confirmed it to CNN.
On Friday Israeli officials told Israel's Channel 10 TV that the American leak as "scandalous" and "unthinkable," The Times notes.
Unnamed U.S. officials also confirmed Israeli strikes on in January and July.
Israeli military analyst Roni Daniel said on Israel's Channel 2 that the leaks remove Israel's plausible deniability and "are pushing Assad closer to the point where he can't swallow these attacks, and will respond."
Israel is publicly neutral in the Syrian war - it asserts the airstrikes target weapons shipments headed for Iranian proxy Hezbollah in Lebanon - but strikes like the one that hit Assad's mountain fortress on May 5 indicate that it is very much invested in what's happening in its neighborhood.