MORE than 100 concerned friends and co-workers have formed a search party for a missing university student following his out-of-character disappearance.

A mass internet appeal and street-by-street search is being carried out for University of Brighton student Diogo Manuel Martins-Alves-Moreira who has not been seen since the early hours of last Tuesday.

His two brothers have flown in from his native Portugal to help with the search.

More than 1,000 posters have been put up between Brighton and Hove, Lewes and Hastings for anyone who might have seen the dependable student and cafe worker.

The 29-year-old Portuguese national, of Prestonville Road, Brighton, was last seen in the early hours of Tuesday morning.

He had visited a friend who lived near to Brighton railway station to watch a movie and left sometime in the middle of the night.

An environmental science and geology student, he has lived in Brighton and Hove for more than five years and has worked at Redroaster cafe in St James’s Street for most of his time in the city.

Friends say there was no dispute when he left the house without his wallet, coat or mobile phone which he had lost days before.

Former girlfriend and flatmate Gemma Doughty said more than 150 people were involved in the search to find him.

She said: “It is really out of character because Diogo is not an impulsive character at all, he’s just a really friendly, really strong character, really grounded.

“He was rally dependable with work, he never took a day off for sickness, never been late to work, so when he didn’t turn up for work on Wednesday we knew something had happened.

“We have got people out on cars, motorbikes, pushbikes and on foot looking for him.”

Friend Jaled Larbi said Diogo had been in good spirits having just returned from a music festival in Leicestershire on the day before he disappeared.

He said: “We really don’t know what to think.

“He's not a man who just disappears for a few days, he’s just a really gentle, polite and dependable man so it’s really worrying.”

Sussex Police have launched a missing person's appeal for the student.

Sergeant Alvin Lee said: "We are becoming increasingly concerned for Diogo as this is totally out of character for him.”

A University of Brighton spokesman said: "We have been contacting students and staff who may know Diogo directly, have published missing person notices on our social media channels and urge anyone who has any information that could help find him to contact the police."