A friend of the family of convicted murderer Arnis Zalkalns has spoken of his horror at hearing of the Latvian's previous conviction and subsequent disappearance in connection with Alice Gross.

Police have this morning revealed that builder Arnis Zalkalns served seven years for murder in Latvia after being convicted in 1998. Detectives say he was also arrested in London in 2009 for indecently assaulting a 14-year-old girl, but no further action was taken.

Victor Mishiku lives on the same road as Mr Zalkalns and his partner Katerina and their one-year-old daughter Linda in Hanwell. He has known the family for over three years and described the builder as 'very quiet and polite'.

Mr Mishiku said: "I know Katerina very well so I was absolutely horrified to hear about the recent developments surrounding her partner Arnis. I saw them only a few weeks ago. Arnis always seemed very quiet but polite. He's not an imposing man, quite unassuming and always very scruffy. He's not particularly tall or well muscled.

"He doted on their daughter Linda. I often saw Mr Zalkalns pushing Linda in her pram on Haven Green. He was holding her last time I was there and would baby sit whenever Katerina was with me as I've been helping her with an illegal eviction case.

Missing Person Arnis Zalkans

"Katerina has been through a lot as she was evicted from her last flat in Southall and lost all her possessions two years ago. I've been helping her with the case and so I know how awful it was for her. She had to go back and forth to the Czech Republic to get help from her family and the council were useless in re-housing her.

"When she had Linda and settled down with Arnis I was very happy for her. Linda is walking now so Katerina has her hands full. She was clearly happy with him and he was a hands on father. I am very shocked to hear about his past. I'm pretty sure she was not with him in 2009 at the time of the alleged assault on the 14-year-old and I doubt she had any knowledge of his previous murder conviction.

"Of course we can't really make any assumptions but this is all very unsettling. There's no proof of anything yet but this all looks very bad."

Detective Superintendent Carl Mehta, from the Homicide and Major Crime Command today appealed for the public’s help in finding missing Ealing resident Arnis Zalkalns who has been named as a suspect in the investigation into Alice's disappearance.

Mr Mehta said: "I need to hear from anyone who knew Arnis whom we have not yet spoken to. His family and work colleagues have stated he was behaving normally in both the days before and after Alice’s disappearance. They are deeply concerned about his disappearance. Arnis has not been seen since Wednesday 3 September. I want anyone who may have seen him after that date, or who may have helped him by giving him money or somewhere to stay, to call and speak to us. It is really important that we trace Arnis and speak to him about Alice’s disappearance."

Anyone who sees Arnis Zalkalns should phone 999 immediately. He may pose a risk to the public.

Arnis Zalkalns went missing a week after Alice and used the Grand Union Canal route to get to work.

Alice, from Hanwell, was last seen on CCTV cameras on 28 August by the same canal route in west London.

Mr Zalkalns was seen on CCTV on 28 August cycling along Brentford Lock at 4pm, some 15 minutes after Alice walked that route. He was last seen on 3 September.

Detectives believe he is likely to have come across Alice as they were both going in the same direction, north along the canal towpath.

Anyone with any information is asked to contact the investigation team on 020 8358 0100, or call Crimestoppers anonymously on 0800 555 111.