Police have launched a fresh appeal for witnesses following the brutal slaying of two young women in the Porirua suburb of Titahi Bay on Friday.

The bodies of Joeline Rangimaria Edmonds, a 21-year-old mother of two, and 16-year-old Jashana Maree Robinson were found by police in house in Morere Street about 10am on Friday.

They were called by neighbours after a heavily blood-stained man was seen running around outside the property.

Ms Edmonds' two children, both under the age of two, were in the house at the time the killings.

Ms Robinson had been a boarder at Ms Edmonds' home for less than a week.

A 28-year-old man, who was granted name suppression, appeared in Porirua District Court yesterday morning accused of murdering the two women and breaching a protection order in respect of Ms Edmonds.

He was remanded in custody until July 7.

The officer-in-charge of the investigation Detective Inspector Shane Cotter said that there had been a good response from the public for help but they still needed "key information".

'We've received some positive responses so far but we're still keen to hear from anyone else who may have information,' he said.

"The public may be able to add something further to what we already know, so it's important that we speak with them.'

Mr Cotter said he was especially interested in sightings of a male carrying a baseball bat, walking between Tawa and Titahi Bay between 6am and 10am on Friday.

The bodies of the two women were removed from the house yesterday afternoon as family members said a karakia.

Mr Cotter said police and forensic scientists were likely to be at the house for a few more days.

Post mortems were carried out yesterday but the results were not expected for several days.