From October, the US Department of Homeland Security will be able to monitor the social media activity and search histories of all immigrants - including permanent residents and naturalized citizens - and anyone they interact with. The US Department of Homeland Security (DHS) has announced it is expanding the kinds of information it collects on immigrants to include social media activity and search histories. The new policy will take effect October 18. The new announcement explicitly speaks of tracking immigrants' Twitter, Instagram and Facebook accounts — although specific search engines aren't mentioned (the phrase "search results" is used three times), leaving it unclear which search engines the DHS will target, and how it intends to obtain the results.