Melb teen may have been stalked pre-attack

A Melbourne teenager raped in her own bedroom by a stranger in a balaclava, may have been stalked by her attacker.

The man entered the Roxburgh Park home just after 7am on Friday and went straight to the 16-year-old's room.

The teen woke to find a man kneeling by her bed before being sexually assaulted for almost 30 minutes.

Police on Monday found items they believe were discarded by the attacker in the front yard of a nearby home, which will be forensically examined.

Detective Senior Sergeant Jason Walsh says police are also investigating whether the man stalked the teen leading up to the attack.

"This guy is not known to the victim, not known to the family, and we have real concerns about that," Det Sen Sgt Walsh told reporters.

"We have concerns this guy has broken into the house ... and then to do what he did."

Her parents were home at the time but unaware of the brutal attack until their daughter raised the alarm.

The "brave young girl" is traumatised and being supported by family and friends, Det Sen Sgt Walsh said.

It's believed the attacker stayed in the area for 10 minutes afterwards so police hope some passers-by may be able to help provide a better description of the intruder.

CCTV footage of the man, captured by nearby houses, is being used in the investigation.

Detectives are expected to remain in the area for most of Monday conducting line searches and speaking to neighbours.