Dublin residents have been left spooked after a massive mysterious bang shook houses and woke locals late last night.
Baffled northsiders took to social media to first see if they were imaging what had happened, asking others if they had heard the noise too, before trying to figure out what the colossal clang was.
And Royal Oak, Santry Court and Woodlawn residents are still none the wiser almost 12 hours after the big boom.
The thud had affects on houses in a 2km radius along the M50 in the area with many fearing it may have been coming from the motorway.
But the only traffic reports near there last night show a breakdown on the M50 slip to R104 at Junction 2 Santry northbound.
But what was it? Here's what residents were saying:
One said: "Anyone else hear a big bang in Santry just now?? Near Royal Oak."
But another protested saying: "No it happened near Woodlawn" while a third piped up and claimed "No you're wrong, it was near Santry Court, we heard a loud boom".
And one worried homeowner even confirmed: "Our whole house shook from it."
While many came to a logical conclusion that it was connected to the breakdown.
One said: "My guess is a blown tyre" while another added: "Yes I am in Woodlawn. Thought it was a banger at first. Might be a tyre blow out from a truck."
Did you hear this last night? Please let us know.
