The devastated mother of a British man who was beaten to death at a German nightclub has described his killers as "not human beings".

Lee Heath, 31, suffered severe head and internal injuries in an attack at the popular u60311 club in Frankfurt in the early hours of Easter Monday.

Police in the city have arrested three bouncers who are being held on suspicion of manslaughter.

A force spokeswoman said officers were investigating whether one of the suspects, a part-time boxer, used hardened "tactical gloves" in the incident.

Mr Heath died in hospital on Wednesday after undergoing several operations.

His mother, Marie Heath, 52, from Silver End in Essex, and younger brother Danny, 28, had flown to Germany to be by his side.

His mother said: "I'm absolutely devastated. I can't describe how I feel at the moment.

"He lived in Germany for 18 months. He loved it here. He was working, he had a good life and he was happy.

"I thought he was safe - I can't believe what's happened.

"We sat by his bedside for two days thinking he would be all right. He's strong, he's young, a good boy, no trouble.

"My 31-year-old baby. It's not right, I shouldn't be burying my baby.

"They've not just killed him, they've killed the family.

"It's never going to be the same again. I just don't know how we're going to move on from this.

"Yesterday I felt like I was dead myself."

Ms Heath said doctors told them her son had a 1% chance of survival.

He was operated on four times in two days as medics tried to stop the internal bleeding.

She said: "He's done nothing wrong. The police have said he wasn't causing any trouble. He was just in the wrong place at the wrong time. He's not in any way to blame.

"Everyone who met him loved him. He's got hundreds and hundreds of friends."

Ms Heath, a driver for people with disabilities, said whoever was responsible for her son's death must face justice.

She said: "They are not human beings. They can't be human beings to do that.

"I need to get justice for my son. I need to know they are going to get what they deserve.

"I can't bring my baby back."

A Frankfurt police spokeswoman said three doormen, aged 35, 32 and 29, were arrested the day after the attack.

She said: "The victim suffered many injuries, including internal injuries and head injuries.

"Three doormen at the club have been arrested suspected of causing these injuries."

She said officers had interviewed about 10 witnesses, adding: "They all said this man was not aggressive. We do not know the reason why the incident started.

"The witnesses said he was walking to get a drink and the doormen grabbed him from behind. We don't know why.

"His girlfriend was in the bathroom and came back when it had all happened so she also doesn't know why it happened."

She added: "One of the men, the 35-year-old, from Greece, is a boxer. He was wearing tactical gloves filled with some hard material, a kind of sand. We have the gloves and will find out if he used them."

Mr Heath, from Hackney in east London, moved to Germany in October 2009 to be with his German girlfriend.

He worked as a decorator and handyman, and advertised himself online as somebody who was "English, friendly, physically fit, organised" and who spoke "a decent bit of German".

His mother said he had just passed his exams and was a fluent speaker. He also leaves behind a sister, Carly, 30.