Green Party MP Caroline Lucas 'monitored by police'
Green MP Caroline Lucas has said a police anti-extremism unit has "monitored" her and a party colleague.
Her appearances at protests are recorded in documents released after a Freedom of Information (FOI) request to police.
Ms Lucas said the tracking sends a "chilling message" to those wanting to take part in peaceful demonstrations.
The National Police Chiefs Council defended the unit but would not confirm who was being recorded.
The file on the Brighton Pavilion MP lists her appearances at political marches and rallies as early as 2007.
A spokeswoman for National Counter Terrorism Police HQ said: "The National Counter Terrorism Police Operations Centre gathers data for policing purposes in accordance with UK law.
"The centre fully complies with stringent data protection legislation in regard to the collation, retention and deletion of records.
"We do not discuss details of records which may or may not have been compiled in relation to named individuals."
Ms Lucas described the monitoring as "a clear waste of public money and resources", adding no-one should be subject to "arbitrary surveillance".
The Green Party said another file lists the political activities of Sian Berry, its candidate in the London Mayor election.
The National Domestic Extremism and Disorder Intelligence Unit website says it was set up to "help reduce the criminal threat from domestic extremism across the UK."
Professor Anthony Glees of the Centre for Security and Intelligence Studies said: "There is a need to keep people under surveillance and there is a need to ensure that people who might be planning acts of extremism, political violence of any kind should be known about by the police.
"But there is no evidence that Caroline Lucas or Sian Berry have been involved in anything that could cause a threat to national security."
In 2014, London Assembly member and Green Party peer Jenny Jones discovered her actions were recorded on a database of "domestic extremists" by the Met Police.