Police hunting for intruder who sexually assaulted girl in Ellenbrook, take man in for questioning

Police forensic officers have spent considerable time searching for clues at and around the Ellenbrook house. (ABC News)

Police hunting for an intruder who sexually assaulted a seven-year-old girl in her home in Perth's north-eastern suburbs have taken a man into custody for questioning.

The development came just hours after police released CCTV footage showing a man climbing a wall around 12:30am on Monday, in an area that detectives say falls into the primary search area in Ellenbrook.

It is not known if there is any link between the man being questioned and the CCTV footage.

No charges have been laid.

'Make yourself known to police'

Earlier on Wednesday, police urged the man in the footage to come forward and asked members of the public to contact them if they had any information about him.

"Police are very keen to talk to that individual. If you are that individual, we ask that you make yourself known to police urgently," Inspector McKenzie said.

"We are getting ever-closer to coming to see you."

CCTV shows a man climbing fence near where a 7yo girl was sexually assaulted.

T-shirt still missing

Inspector McKenzie confirmed police had located a flyscreen from the house where the girl was attacked and that the screen was undergoing forensic testing, but a T-shirt taken from the girl's bedroom had not been located.

"We still request any members of the public to keep an eye out for the shirt, whether it may be in their front yard of their premises, or located in a park nearby," he said.

"We ask if anybody sights that shirt to contact Crimestoppers straight away and we will send investigators out there to retrieve that evidence."

The girl's pyjama top is still missing. (ABC News)

The girl has been released from hospital, and has spoken to a specialist child interviewer.

Inspector McKenzie said he had spoken to the family.

"Under the circumstances, they are holding up well but, of course, this is every parent's worst nightmare," he said.

"They are being well supported by police and child advocates as well, who are dealing with the family and the children.

"They are being offered every support that we possibly can [give]."

Police have spoken to registered sex offenders, with high-risk people being prioritised.

WA mounted police officers have been scouring the area for clues. (Supplied)

Anyone who has information, including dashcam or CCTV vision from the area between Sunday night and Monday morning, is urged to contact Crime Stoppers on 1800 333 000 or, online, at crimestopperswa.com.au