A man reportedly armed with a knife has been shot dead during a stand-off with police at Ipswich train station, south-west of Brisbane.

Acting Superintendent Mel Adams confirmed one man died at the scene, and an Ethical Standards Command investigation was in its early stages.

In response to questions about the number of shots fired during the incident, about 4.15pm on Sunday, Superintendent Adams said she was not prepared to go into details as it was “too early in the investigation”.

“It’s really a tragedy here this Sunday afternoon," she said.