US President Donald Trump announced Friday that a senior department official, Chad Wolf, would become the nation's new acting homeland security chief, a role at the centre of his crackdown on undocumented immigration.

Donald Trump announces new acting US homeland security chief

A US federal judge on Monday blocked President Donald Trump's policy of returning asylum seekers to Mexico to wait out the processing of their cases, saying the Department of Homeland Security had overstepped its authority.

US judge blocks Trump's policy of returning asylum seekers to Mexico

Haftar should immediately halt military operations on Tripoli: Pompeo The United States is "deeply concerned" by fighting near Libya's capital Tripoli and is seeking an "immediate halt" to an offensive by strongman Khalifa Haftar, Secretary of State Mike Pompeo said on Sunday.

News brief: Big stories of the day

US Homeland Security Secretary Kirstjen Nielsen, the front-line defender of the administration's controversial immigration policies, announced her resignation Sunday, in a move linked by observers to the president's anger over Central American border crossers.

US Homeland Security chief Kirstjen Nielsen resigns

US President Donald Trump is expected to remove Department of Homeland Security chief Kirstjen Nielsen and is considering replacing chief of staff John Kelly in another shakeup of his administration, a source close to the White House said.

Trump may fire Homeland Security boss, replace chief of staff: Source

Authorities found two more suspicious packages on Friday addressed to US Senator Cory Booker and James Clapper, the former US director of national intelligence, amid a manhunt for the person who sent bombs to prominent Democrats and critics of US President Donald Trump.

Police find packages sent to ex-US intel chief Clapper, US Senator Booker

China is waging an unprecedented campaign to influence American public opinion as November congressional elections approach and presents the greatest long-term counterintelligence threat to the United States, US security officials said on Wednesday.

China trumps Russia in counterterrorism threat to US: FBI Director Christopher Wray

The Texas National Guard said it would send 250 troops to the border within 72 hours and had already deployed two Lakota helicopters, while Arizona's governor said he would send 150 personnel next week

Texas, Arizona announce troop deployments to Mexico border

President Donald Trump, unable to get the US Congress or Mexico to fully fund his border wall, will post National Guard troops along the Mexican frontier, officials said on Wednesday, in a move that was likely to escalate tensions with a key US ally

Trump, stymied on wall, to send troops to US-Mexico border