Detained student activist Mahmoud Khalil appears in US immigration court

Mahmoud Khalil appeared in court on Friday (Ted Shaffrey/AP)

Detained Columbia University student activist Mahmoud Khalil appeared briefly on Friday in immigration court at a remote Louisiana detention centre as his lawyers fight in multiple venues to try to free him.

Mr Khalil, 30, a legal US resident with no criminal record, sat alone next to an empty chair — his lawyer participated via video conference — through a brief court session that dealt only with scheduling.