One of the foghorns on the Golden Gate Bridge malfunctioned and blared continuously early Friday morning, a bridge spokeswoman said.
The relay switch on one of the horns located near the south tower of the bridge needed to be repaired and sounded its alarm continuously early this morning, bridge spokeswoman Mary Currie said.
Another set of foghorns is located mid-span, Currie said.
The horn was turned off by 3 a.m. and repairs were made and completed around 8 a.m.
Currie said a bridge electrician was able to get permission from the U.S. Coast Guard to temporarily disconnect the alarm to make the fix.
The early-morning alarm prompted many within earshot to write about the loud sound on social media.
Several people on Twitter wrote around 2 a.m. about the nonstop foghorn.
One user wrote, "Is there some sort of 2 a.m. #foghorn concert in SF tonight? Either that or someone passed out on the horn. 20 minutes without a pause now."
Another person wrote a series of tweets around 2:20 a.m. about the unusual blasts, including, "What's with the never-ending fog horn in the SF bay right now... #rude" and "Omg. This can't be happening at 2 a.m. It can't be THAT FOGGY #foghorn #shutitdown."