Police have re-released CCTV footage of two suspects a year after a man was raped and robbed following a night out in Watford town centre.

The 21-year-old victim was sexually assaulted in Riverside Road around the park area at approximately 3.30am as he walked home alone on June 22 last year.

Hertfordshire Constabulary said two men approached the victim and he was forced to perform a sex act.

They then demanded money from him and marched him to different cash machines in the town centre.

No arrests have been made in the case despite several publicity drives, including on BBC’s Crimewatch where the victim’s mother made an appeal to catch the attackers.

Speaking on the programme, which aired in November, she said: "My son would never have been walking home in that area if he hadn’t of thought he was safe. And to find out that there are people around that do this sort of thing and could actually do it again is really, really scary.

"He was not a one off, it does happen. But lots of people, if it does happen to them, they don’t report it. And I think my son has been very, very brave and I am very, very proud of him to have reported it."

The men the police want to speak to are described as white, slim and both around 6ft tall, with short hair.

At the time one had been carrying a shovel which was used to threaten the victim. This suspect was wearing a lightly padded black hooded gillet with a yellow trim around the arms and a distinctive "New York" motif on the back. He was also wearing a dark coloured t-shirt, light blue jeans and white trainers.

The other male was wearing a pastel checked short sleeved shirt, dark blue jeans and brown shoes.

Following the latest appeal, Detective Constable Louise Cleary said: “We have made a number of local and national appeals for information to identify the two men pictured and on the anniversary of this extremely serious and distressing incident I would once again ask members of the public to please contact us if they can help.

“Somebody somewhere must know who these people are and I would urge them to please call police with information. If you do not feel you can talk to police then please do call Crimestoppers, they will never ask for your name or take any personal details.”

Anyone with information is asked to contact the Hertfordshire Constabulary via its non-emergency number 101 quoting crime reference number C1/13/2962.

Alternatively call Crimestoppers, the independent charity, anonymously on Telephone 0800 555 111.