Iran is one of the most censored countries in the world. Criticism of the system of government, its members and institutions, as well as the supreme leader and religion, are not tolerated. Both traditional press and the internet are tightly censored, and authorities exercise control over content and reporting. Media outlets which fall foul of the Government of Iran may be closed or have their publishing licenses suspended. The government also uses mass and arbitrary detention to silence dissent. 19 journalists were jailed in 2015, making Iran the seventh worst jailer of journalists in the world. They were prosecuted primarily on national security charges such as "espionage," "acting against national security," and "cooperation with foreign embassies", as well as for crimes such as “insulting Islam”, or “spreading propaganda”. In recent years, the government has targeted online activity, blocking scores of websites and arresting and imprisoning bloggers and individuals on the basis of their online expression.