Trafalgar Square in London was briefly evacuated by police on Saturday following a report of a suspicious car.
It comes as London enters the third day of events to celebrate Queen Elizabeth II’s Platinum Jubilee.
Shortly after the evacuation, police removed the car and said the incident was not terrorism-related.
In two chains of updates on TwitterCity of Westminster Police said they received a report from a member of the public at 9.22am of “a suspicious vehicle” in Trafalgar Square.
The iconic square in central London is less than a mile from Buckingham Palace, where the Queen resides and where a concert is due to be held on Saturday night.
The force said at 11:06 a.m. officers had evacuated the scene and asked people not to come to the area.
Ten minutes later, he said the incident was over and the square should reopen in due course.
A police car carrier was seen at the scene carrying a car.
Police said officers had “no further concerns” after investigating the incident, which they said “was not terrorism related”.
“We encourage everyone to share with the police any concerns they may have while traveling. Please remain vigilant,” police added.
A police spokesman said earlier the force was carrying out extensive checks in the area.
At 7.40pm on Saturday, the BBC’s Platinum Party at the Palace concert is due to take place at Buckingham Palace as part of celebrations marking the Queen’s record 70-year reign.
The Queen’s son and grandson, would-be future kings Prince Charles and Prince William, are expected to pay their respects to the Queen at the star-studded outdoor concert.
The four-day Jubilee Festival began on Thursday, which also marked the 69th anniversary of the coronation of Elizabeth, who became queen on the death of her father George VI in February 1952 and head of state of 14 other countries, including Australia , Canada, and New Zealand.
She has now been on the throne longer than any of her predecessors in 1,000 years and is the third longest reigning monarch of a sovereign state. Opinion polls show that she remains hugely popular and respected among Britons.
Reuters contributed to this report.