Police are investigating the death of a young documentary maker who was sleeping rough in freezing temperatures to highlight the plight of the homeless.

Lee Halpin, 26, had planned to spend a week living on the streets in his home city of Newcastle.

He began the project on Sunday but was found dead three days later in a derelict building in the West End of the city.

How he died has not yet been confirmed but it is believed he may have died from hypothermia.

Speaking on a YouTube video the night before his week of sleeping rough began, Mr Halpin said the project was part of an application for a Channel 4 investigative journalism scheme, to give an example of fearless reporting.

He said he had spoken to a homeless charity about the rise in the number of people on the streets and the effect of changes to Britain's welfare system this month.

"I'm about to go and spend a week being homeless in the West End of Newcastle. I will sleep rough for a week, scrounge for my food, access the services that other homeless individuals use," he said.

"I will interact with as many homeless people as possible and immerse myself in that lifestyle as deeply as I can."

He concluded the video by saying he hoped it showed his willingness to get to the heart of a story.

A Channel 4 spokesperson said: "We are saddened to learn of the tragic death of this aspiring young journalist. Our thoughts are with his family."

Mr Halpin's friend of 10 years, Daniel Lake, said: "I was just talking to Lee on Saturday, having some banter talking about football and how excited he was about going out filming.

"Lee was a great guy, a character and was well known. His big things were creative writing and poetry ... He made the ultimate sacrifice trying to raise awareness about what was happening to other people."

Friends and supporters have left tributes on the Save Newcastle Libraries website, to which he was a contributor.

One said: "He was a credit to the North East and all he did was give."

Northumbria Police have arrested two men in connection with the death.

The men, aged 26 and 30, were arrested on suspicion of supplying a controlled drug and have since been bailed pending further inquiries.