Six people have been arrested over a suspected plot to disrupt the London Stock Exchange, the Metropolitan Police has said.
The force said it began its investigation after receiving information from the Daily Express on Friday.
Activists from a group called Palestine Action were allegedly intending to target the exchange on Monday morning.
It is claimed they were intent on causing damage and were going to “lock on” in an attempt to stop the building from opening for trading.
It may have been “one part of a planned week of action”, said Detective Superintendent Sian Thomas.
The Met is coordinating with other forces to “ensure that appropriate resources are in place to deal with any disruption in the coming days”, Ms Thomas added.
In the early hours of Sunday, officers arrested a 31-year-old man in Liverpool on suspicion of conspiracy to cause criminal damage.
A further five people, all believed to be part of the same plot, were arrested later on Sunday for the same offence, Scotland Yard said.
A 29-year-old woman was arrested in Brent, and a 23-year-old man was arrested in Tower Hamlets, London.
Two women, aged 28 and 26, were arrested in Liverpool, while a 27-year-old man was arrested in Brighton.
All six remain in custody.
Pro-Protesters in central London on Saturday
“These are significant arrests,” Ms Thomas said.
“We believe this group was ready to carry out a disruptive and damaging stunt which could have had serious implications had it been carried out successfully.
“I’m grateful to the Express for their willingness to provide the information gleaned from their own investigation.
“It was instrumental in helping us to intervene successfully.”
On Saturday, thousands of pro-Palestinian protesters marched through central London.
It was one of many such events since the attacks by Hamas in Israel on 7 October, and Israel’s subsequent military operations in Gaza.