Two people have been killed and dozens are reported injured in a train accident near Pretoria's Mountain View train station.

The accident is believed to have occurred when two trains collided on Tuesday morning during the early morning rush hour commute.

"At the moment it appears that two people are dead, with a heck of a lot more badly injured. Emergency services are trying to reach the injured who are trapped inside the carriages," said a Pretoria police officer, who asked not to be named.

Netcare 911 spokesperson Shawn Herbst said its paramedics were alerted shortly before 10am on Tuesday.

"Reports from the scene indicate that on initial assessment two people had sadly died, two sustained critical injuries and had to be flown to hospital via helicopter.

"Approximately another 200 patients sustained minor injuries," Herbst said.

"Circumstances leading up to the collision are at this stage unknown, however rail authorities and law enforcement have control over the incident," he added.

Metrorail spokesman Lillian Mofokeng could not immediately be reached for comment.

This is a developing story.