The vast majority of those detained Saturday were arrested for displaying placards declaring their support for the banned group, known as Palestine Action. Home Secretary Yvette Cooper, who oversees law enforcement in Britain, rejected that characterization, saying Palestine Action was outlawed after committing serious attacks involving violence, significant injuries and extensive criminal damage. Palestine Action previously targeted Israeli defense contractors and other sites in Britain that it believes have links with the Israeli military. I support Palestine Action.” That was enough for police to step in. The government moved to ban Palestine Action after the activists broke into an air force base in southern England on June 20.