Swedish woman, 70, accused of locking up her son for 28 years

The man, now in his forties, was found with injuries, sores and almost no teeth

The man was found lying under a blanket on the floor of a flat to the south of Stockholm.  AFP 

A woman, 70, was arrested on suspicion of keeping her son captive for 28 years, after a malnourished man was found in a flat in Sweden.

The man, now in his forties, was found on Sunday lying under a blanket on the floor by a relative in an apartment block south of Stockholm.

He was described as having injuries and sores, almost no teeth, and his speech was slurred.

He was taken to hospital but his injuries were not life-threatening.

Prosecutor Emma Olsson, who is leading the preliminary investigation, said the woman was arrested on Monday on suspicion of unlawful deprivation of liberty and grievous bodily harm. The woman denied the charges.

Ms Olsson said the relative alerted authorities after finding the man.

The relative went to the flat after finding out the mother had become ill and found the door was unlocked, Swedish media reported.

There was "urine, dirt and dust" all over the place and "it smelt rotten", he told local newspaper Expressen.

He heard a noise from the kitchen and found the man.

“He spoke very fast and a little incoherently, but he was not afraid of me,” the relative said.

The man was imprisoned for 28 years, meaning he would have been 13 when it started, Expressen reported.

Ms Olsson said investigators would interview the mother, son and witnesses.