Everyone knows that feeling. You might just be wandering back from the shop, but it's late, it's dark, and there's no one about.

You hear footsteps behind you and your heart starts beating faster. You speed up, and try to glance around so you can assess the threat.

Then, just when you're starting to panic, you realise you're back at your doorstep and it's all OK.

Statistically, the chances of anyone being attacked by someone they do not know are tiny, and attacks by strangers make up just eight per cent of all rapes.

But women still feel under threat, and high-profile cases bring home the message of just how dangerous the streets can be at night.

Last Thursday, Steven Wright was convicted of murdering five women in Ipswich. The next day, Mark Dixie was jailed for life for raping and murdering model Sally-Anne Bowman in South Croydon. On Tuesday this week, Levi Bellfield was convicted of murdering two women in London, and named as the prime suspect in the disappearance of 13-year-old Millie Dowler in Walton-on-Thames in 2002.

Closer to home, Accrington paedophile Samuel Cree was jailed indefinitely this week for a terrifying sex attack on two 11-year-old girls.

Detective Chief Superintendent Mick Gradwell, of Lancashire Police, has investigated some of the county's most sickening crimes, and said women were right to be on their guard. Despite their rarity, the very nature of such attackers means they can strike at any time, anywhere, and without warning.

Mr Gradwell said: "Thankfully, stranger attacks and violent crimes of this nature remain very rare in East Lancashire, but they are scary simply because they are so random.

"Although you could quite happily walk down an unlit street or through a park at night and nothing happens, you have that fear that it could.

"Obviously, you can't predict where a random attack will take place. If someone becomes a serial attacker, they are likely to take time to choose their victim, location and time to their convenience, and that's why they are so dangerous."

He said woman could feel safe on East Lancashire's streets providing precautions were taken.

"It helps if people are aware of their own personal safety," he said.

"Women should be aware of the routes they are taking and make sure they are walking in well lit areas.

"They should also make other people aware of where they are and what time they should be expected home. You can be safe anywhere in the world, it's a matter of taking the necessary precautions.

"When attacks happen a lot of work is done by police to allay the public's fears. It's about being honest and open with the public, warning them of what's happened and appealing to the public for information."

Wright, Dixie and Bellfield are all believed to have attacked women before, and Samuel Cree had been released early from prison after an indecent assault on a 12-year-old, before attacking his two latest victims, but Mr Gradwell said even previous offences could not always identify a future serial attacker.

He said: "There are lots of people who commit relatively minor offences, but very few will go on to become a predatory offender. You can have 10 individuals and not know for certain if all 10 of them or none of them are going to commit predatory attacks, and you can't keep them all in jail forever because of something they might do in the future."

But DNA testing has made it easier for police to identify the culprit from a group of suspects, and has even helped officers catch killers and rapists from decades ago.

Both Dixie and Wright were brought to justice thanks to DNA profiling. The database also helped provide the link to a third attack committed by Great Harwood rapist Shaun Greenwood.

Samples were taken from his arrest for attacks on women in Nelson and Burnley in 2005 and matched a partial DNA profile left by the rapist after an attack on a Great Harwood teenager over three years earlier.

Mr Gradwell was also part of the investigation that caught Graham Darbyshire, the notorious Witton Park rapist. He had brutally raped a 22-year-old woman in the Blackburn park in October 1995, but was not convicted of the crime until 2006, when a police cold case review team matched his DNA to the attack.

In court, he also pleaded guilty to a 1993 sex attack in Greater Manchester. He had already been convicted, in 1986, of a rape in Blackpool. Mr Gradwell said: "DNA helped us catch him, and it was also very important in both the Wright and Dixie cases, but it's for the people to debate and decide whether everyone should be on a database.

"Cases like these highlight the benefits to it - having those men's DNA meant the police could catch them - but I can also fully understand why some people think it's an infringement on human rights.

"But DNA is not the only answer and for any attack like this the force's major investigation team would be involved, with massive resources allocated to catching the person and preventing future attacks. That has always been the case and it is never going to change."

Rachel Horman, head of domestic violence and a partner at Watson and Ramsbottom solicitors, said: "The risk of an attack is small, but it's all about your perceptions and if you feel safer and act more confidently that can have a big effect - if a woman looks nervous, they are more likely to be targeted.

"Women should do whatever they need to make them feel more confident - whether that's a personal alarm or something like self-defence classes."