Dozens of protesters stormed an office in London's West End today.
The group from Occupy London - the anti-capitalist protesters camped out in the churchyard of St Paul's Cathedral - said they were "targeting" Mick Davis, the CEO of mining company Xstrata.
An Occupy London spokesman said they were aiming the demonstration at Mr Davis because he was the highest paid CEO of all the FTSE 100 companies in the last year.
A group of 60 demonstrators entered Panton House, in Panton Street - which houses offices of Xstrata.
Some of them gained access to the roof, where officers moved in to clear them.
"When his companies had losses and the economy collapsed, he received £18,426,105 for his efforts," the spokesman said.
He said that around 20 protesters were being held inside by riot police and that a "few hundred" were being kettled in the street outside - a number of them were holding UK Uncut placards.
Police sealed off the area around Panton Street and marched through the 200-300 protesters, to shouts of "Shame on you".
Karen Lincoln, supporter of Occupy London, said: "Mick Davis is a prime example of the greedy 1% lining their own pockets while denying workers pensions.
"In this time when the Government enforces austerity on the 99%, these executives are profiting. The rest of us are having our pensions cuts, health service torn apart and youth centres shut down.
"We refuse to stand by and let this happen. We call on others to join us in the fight for a more just society. Today we have taken this to one of the offices of the 1%."
Police said they are in the process of making a number of arrests for aggravated trespass.
A Scotland Yard spokesman said: "At approximately 3.50pm a containment was put in place outside Panton House, Haymarket, to prevent disorder by a group ofprotesters outside the building.
"Some protesters have entered the building and officers are in the process of making arrests for aggravated trespass."
Mr Davis, 52, was appointed chief executive of Xstrata in 2002.
An Xstrata spokeswoman said: "Xstrata confirms that a number of protesters have attempted to enter the company's offices in central London today.
"All executive pay is approved by the company's shareholders and is linked to company and individual performance.
"Last year Xstrata delivered its second best financial performance since inception, with an 86% increase in profits, record cost savings, improved safety performance and total shareholder returns substantially greater than the FTSE 100 average."
Some of the protesters who gained entry to Panton House ran to the top floor of the building, where about 15 of them held a banner stretching across the building that said: "All power to the 99%".
Police formed a line between the protesters and the building.
As protesters were kettled, a pink smoke grenade was thrown at the doors of the building.
The diversion to Panton House is said to have spread by word of mouth on the march, beginning with a minority of protesters.
Greg Foreman, a 23-year-old student, was kettled at Panton House.
He first heard about plans to divert to Panton House as the march reached the Millennium Bridge.
He said: "More than 100 people came down Haymarket at about 4pm. I didn't know that was going to happen. I didn't know what Panton House was.
"If I knew the place and I knew the injustice maybe I would have thought about (going inside).
"For all I know it might have been a nursery."
Police are slowly releasing protesters from the kettle on Panton street.
- More about: