Some residents in Suffolk got an early morning wake-up call in the form of a siren sounding off.

"About 3 a.m. in the morning I was laying in bed and all of a sudden it goes off," says Liz Loper, of Coram.

Loper says she knew it wasn't a fire department siren.

Coram resident Laurinda Manos says the mysterious siren blared for more than 40 minutes.

"I heard it right away and you know it was like an oscillating type of siren sound. It would get louder and lower," says Manos. 

Neighbors took to social media hoping to get an answer as to where the siren noise was coming from. Residents say they heard the siren again around 11:30 a.m.

Some were concerned that the siren sound was coming from the Shoreham Nuclear Power Plant, which was decommissioned in 1989.

News 12 called PSEG-LI and a spokesperson said there was no reason to be alarmed.