A string of unsolved rape cases are to be reopened after a hooded rapist who carried out terrifying sex attacks on six women was today jailed for 20 years.

Timothy Din, 44, wore a black balaclava as he selected slim young women with shoulder-length hair in six frighteningly similar strikes on Teesside.

Police discovered that Din, a married-father-of-five, had a mistress and an insatiable sexual appetite.

Burmese-born Din was first arrested on suspicion of rape in 1991 but then released.

Detective Inspector Stewart Swinson of Cleveland Police who led the latest investigation said after the case: "It is extremely rare for sex attackers to wear balaclavas. He has a distinctive appearance which he took great care to try and hide through wearing a balaclava.

Five of his Teesside victims were asleep in homes in Thornaby on Teesside, which taxi fleet mechanic Din almost certainly knew were unlocked, said prosecutor Aidan Marron QC.

On two occasions Din found his victims asleep with young children, and threatened to harm the youngsters to force them into submission.

Police investigating the attacks, between November 1999 and December 2000 in Thornaby, Teesside, found matching earrings in his home.

He raped a 22-year-old mother-of-two who had been asleep in bed with her three-year-old daughter when she was wakened by a hooded attacker with a beer belly at 3am on November 23 1999.

Din of Yeovil Walk, Hartlepool, was found guilty of rape, three attempted rapes, and burglary with intent to rape between November 1999 and December 2000. One victim would not make a complaint for fear of the court ordeal.

Din was also ordered to register as a sex offender for life and the judge said that when he was released he should be kept under the closest supervision. Judge Peter Fox QC told him: "The invasion of a lone woman's home in the still dark hours of the night in order to rape her is an appalling outrage.

"Six such attacks over a period of 18-months implies only that you are and will long continue to be serious public danger.

"Your past history contains information of such proclivity. What you did on each occasion seen as the jury now indicates was terrifying for the young women concerned, and its consequences long-term are not to be under-estimated.

"You prepared each attack with very great care and over a very long period. You must have watched and waited to seize such opportunity. You also had your defence very well arranged in each case."

Din's wife Lynne was not in court when he was sentenced, but his blonde mistress was. After the verdict he repeatedly mouthed at her: "I didn't do it," but she responded with: "Yes, you did."

Acting Superintendent Stewart Swinson said later: "He is a sexual predator who identifies his victims, builds a picture of their lifestyles and when they are at their most vulnerable he attacks them.

"All the attacks were calculated and well planned. Her was arrested for a series of rapes in 1991 in Hartlepool. Police will be looking at a number of previously unsolved rapes in the Cleveland area."