The car belonging to one of the three women who vanished after a night out on Friday is reportedly still parked outside the nightclub where they were last seen.
Fears are growing for Sophie Russon, Eve Smith and Darcy Ross, who have been missing since the early hours of Saturday morning.
The 20-year-olds have not been seen since 2am on Saturday morning after going out in Newport, South Wales.
Two men, Shane Loughlin and Rafel Jeanne-Actie, are also understood to be missing, reports Wales Online.
They have all not been active on social media or on their mobile phones for nearly two days.
Body of boy, 5, missing for three months recovered from fast-flowing riverThe women were enjoying a night out at the popular bar Muffler before going to clubbing hotspot Trecco Bay in Porthcawl.
It is not clear if the five all went out together, or if they met during the evening.
Ms Smith’s car is still at the venue, according to her worried sister Lauren Doyle.
Police are searching for the three women and two men, who have not any contact with the families or friends for over 40 hours.
One of the young women's family members said it was out of character for them to go off the radar as frantic friends search between Cardiff and Newport for them.
Ms Doyle says all five have all been reported missing to police, who are searching for them all.
She said: “It is known that they went to the Muffler in Maesglas and then went to Trecco Bay on Friday night but left there to an unknown location during the night.
"They were last seen at approximately 2am.
“None of them have made contact with friends or family, which is very unusual. We are all worried sick and thinking the worst.”
She added: "Eve's bag is with my mum, this contained her car keys and bank card. This means Eve has no access to funds or her vehicle.
Man, 54, charged with murder of 24-year-old woman mssing for over three weeks"All five persons pictured have now been reported missing and are officially missing people."
Tori Preece, Ms Russon's aunt, said: “My niece and her friends have been missing since Friday night. There has been no contact and no social media presence since the early hours of Saturday morning.
“They were at the Muffler in Maesglas until around 11:15 then went to Trecco Bay until around 2am. They are not girls who take unnecessary risks and are always in close contact with their families.
“All of the families involved are extremely concerned. The Police are involved and they have been recorded as missing persons."
A relative of Mr Loughlin has also confirmed he is missing.
His sister, Carly-Louise Chivers posted: "Has anyone heard or seen my brother Shane Loughlin? He hasn't been in contact. Let me know ASAP, please."
His family say they are currently working with the police to try and locate him.
The Mirror has contacted Gwent Police for a statement.
A spokesperson confirmed to WalesOnline that the force is investigating.
A spokesperson for Trecco Bay Holiday Park also said: “We are aware of reports of five missing people. None of these people were registered guests at the park, however we are assisting police with their enquiries.”