A former soldier being held on suspicion of murdering teenage mother-to-be Nikitta Grender remained in custody today after detectives were given extra time to question him.
Police now have until tomorrow morning to either charge or release a 26-year-old man, who was arrested on Wednesday.
The heavily pregnant 19-year-old was attacked at her flat in Broadmead Park, Liswerry, Newport, South Wales, on February 5.
She was stabbed twice and her flat set on fire by her killer in a desperate bid to destroy evidence.
Yesterday, Gwent Police detectives investigating the brutal murder appealed for help in locating Miss Grender's missing Samsung Tocco SF80 mobile phone.
They also revealed that attempts to trace four people captured on CCTV in the Broadmead Park area had been successful.
Three of the four potentially vital witnesses have come forward and officers received around 36 calls connected with the appeal.
One remaining potential witness, seen walking on Fosse Road, Pontfaen, at 5.59am, has yet to come forward.
"That person could well hold vital information. Police would like him to get in touch as he may have seen something relevant to the investigation," a police spokesman said.
Det Supt Geoff Ronayne, who is heading the investigation, said: "Although intensive searches have been carried out over the last few days, we have yet to find Nikitta's mobile phone, a Samsung Tocco SF80.
"We had a very good response from the appeals we made yesterday and three out of four people captured have already come forward.
"We are grateful to the local community for their response to the media appeals."
Last night, magistrates granted police an extra 24 hours to question Mr Whant, who worked as a bouncer in Newport. The custody time limit for the latest extension runs out at 6am tomorrow.
His arrest came as police revealed two knives had been recovered in the hunt for the murder weapon, believed to be a knife.
Both have been sent away for forensic examination.
Miss Grender was due to give birth to a baby girl less than two weeks after she was murdered.
She and Mr Mayes had moved into their flat six months before and had decorated a room for the baby, already named Kelsey-May.
Officers are expected to return to the murder scene today to continue extensive searches on the estate where the couple lived.
Searches yesterday continued at two out of six premises which have been searched across the city. Police also made further house to house inquiries.