The popular tourist attraction, the Science Museum in London, has been evacuated, according to its official social media.
A post on the museum's official twitter at 12.05pm today read: "The museum has been evacuated as a precaution.
"Our priority is the safety of our visitors and colleagues. We will provide an update shortly."
And visitor Megan added: "Been so excited for the Science museum for three days, get inside and within five mins the whole place gets evacuated and alarms going off, police turning up, what on earth is going on."
And Mark on Twitter replied to ask if there was any update as there were "500 school kids" outside waiting to get in.
The Daily Mirror spoke so the Museum directly, but they were unable to provide us with any update.
Are you at the Museum? Email us at webnews@mirror.co.uk
A spokesman for the Met Police in London said a fire alarm had gone off in the building and officers were there as a precaution.
The museum is on Exhibition Road in the South Kensington area of London and host more than three million visitors a year.
Entry to the museum is free and it is usually open Wednesday to Sunday from 10am to 6pm.
The museum further tweeted: "An engineer is on site looking into what caused the alarm system to trigger.
"We thank visitors for their patience and will be in touch with ticket bookers affected.
"We will provide a further update on reopening as soon as we are able."
