More than 500 people have been charged with immigration violations in the United States over the past two years, after an initial report linked them to a terrorism or homeland security threat, The Washington Post reported on Monday, quoting previously undisclosed government figures.

Immigration laws can provide a quick, easy way to detain people who could be planning attacks, as terrorism charges can be difficult to prosecute, Homeland Security officials were quoted as saying.

Authorities have also used routine charges such as overstaying a visa to deport suspected supporters of terrorist groups, the report said.

Muslims and civil liberties activists argued, however, that US authorities are enforcing minor violations against Muslims and Arabs, while ignoring millions of other immigrants who flout the same laws.

Many of those charged are shown not to be involved in terrorism, they noted.

Before the Sept. 11, 2001 attacks, immigration agents were minor players in counter-terrorism in the US, but that changed during the investigation of the hijackings, when 768 suspects were secretly processed on immigration charges. Most were deported after being cleared of connections to terrorism.

Before the attacks, there were only 50 immigration agents on Joint Terrorism Task Forces across the country, but the task forces now include more than 200 such agents who report to an ICE Counter-terrorism Section in Washington, the report said.

Source: Xinhua