The boyfriend of missing nightclubber Sian O'Callaghan today made a tearful appeal for information to find her.

The 22-year-old was last seen about 2.50am on Saturday as she left the Suju club in Swindon, Wiltshire, alone.

Fighting back tears, Kevin Reape told a police press conference at Gablecross Police Station: "I just want to say how worried we are about Sian.

"Someone out there must know where she is.

"This is a terrible time for all of us and we are hoping for her safe return."

Mr Reape, 26, a quantity surveyor, tearfully told reporters: "I just want to say how very worried we are about Sian. She has been missing now for over two days and it's not like her to not come home or contact anyof us for such a long time.

"We all want to know where Sian is and we want her home safe and well. Sian is a bubbly, lively person and is instantly liked by everyone she meets.

"She is very close to her family and has lots of friends. We'd like to thank all of the people who have shown us support and helped search for Sian.

"Their kind words and gestures have been a great help to us.

"Someone out there must have seen or known where she is and we just want them to come forward and contact the police.

"This is a terrible time for all of us and we are praying for Sian's safe return.

"If Sian is listening and doesn't want to contact us I beg her to at least ring the police.

"We are all really grateful for the media coverage which we are sure is helping to spread the appeal but after the conference today we would really like to be left alone to deal with this difficult situation.

"We all just want to know that she's OK as it's breaking our hearts not to know where she is."

Miss O'Callaghan's brother, Liam, 24, added: "Sian means the world to us and we just want her come home.

"If anyone has any information please help the police and come forward."

Also present at the press conference today were Miss O'Callaghan's parents Mick, 51, and Elaine, 48, and younger sister Lora, 19.

Police have been searching a 4,500-acre forest for signs of Miss O'Callaghan whose disappearance has been described as totally out of character.

She has not made contact with any friends or relatives since, causing police to become increasingly concerned.

Her phone was later used in Savernake Forest near Marlborough, 12 miles away.

Officers spent yesterday combing the forest for information on Miss O'Callaghan's whereabouts, staying there until nightfall.

Miss O'Callaghan had been on a night out with girl friends at the Japanese-themed club before she went missing.

Her boyfriend Mr Reape was not out with them and raised the alarm at 9.45am on Saturday morning when she had not returned home.

Savernake Forest, where police have focused their search, is between Marlborough and Hungerford and is privately owned by the Earl of Cardigan and his family.

There is also an increased police presence in the town as the investigation into Miss O'Callaghan's disappearance continues.

Miss O'Callaghan is described as being white, 5ft 3in tall, of medium build, with brown hair cut in an asymmetric style and green eyes.

She was wearing a grey dress, black bolero-style jacket, dark tights and flat boots when she was last seen, and was carrying a dark handbag with a beige flower attached.

Concerned friends have set up Facebook groups and appealed for help on Twitter.

Wiltshire Police confirmed Miss O'Callaghan was assaulted in the toilets of the same nightclub in October 2008, when another woman punched her.

Anyone with information on Sian's whereabouts should contact Wiltshire Police on 0845 408 7000 or, anonymously, on Crimestoppers 0800 555 111.