Police swooped on a 'suspicious vehicle' parked outside Buckingham Palace this afternoon.
Tourists were told to move as a police cordon was put in place in front of the famous London building.
A section of the Mall was also cleared, the Mirror reported. Specialist officers raced to the landmark, but stood down a short time later.
The City of Westminster Police confirmed the incident in Constitution Hill was "deemed to be non-suspicious" around 2.45pm.
They added: "The incident has now being stood down and cordons are in the process of being lifted. Thank you for your patience."
Footage posted on social media shows police clearing an area on the Mall, as well as officers chasing police down Marlborough Road.
Passersby told how officers screamed at people to move as they quickly cleared the area to make it safe.
