The head of the US Border Patrol has slammed as “completely inappropriate” sexually explicit posts about Rep. Alexandria Ocasio-Cortez and comments questioning the authenticity of a photo of a drowned man and his young daughter in a secret Facebook group for agents.

New medical checks have been carried out on nearly every child in Border Patrol custody, US immigration authorities have said.

The investigation into the death of a US Border Patrol agent has yielded no evidence that there was a "scuffle, altercation or attack", FBI officials said.

The US Border Patrol chief has been forced out a day after President Donald Trump announced an ambitious plan to build a wall at the Mexican border and hire 5,000 Border Patrol agents, according to a US official.