http://www.dailymail.co.uk/news/art...ckers-police-realise-powerless-stop-them.html More than 500 women were assaulted or robbed by mobs of migrant men The harrowing cries of a girl can be heard on the video from New Year's Eve Video also shows fireworks being launched into huge groups of people Another victim of sexual assault has come forward with her recollection Newly-released footage from the New Year's Eve sex attacks in Cologne show how powerless the vastly-outnumbered police were in handling the out-of-control crowd. More than 500 women were assaulted and robbed by mobs of immigrant, mostly North African men in the German city during last year's New Year's Eve celebrations. Harrowing cries of a girl shouting: 'No! You cannot touch me!', can be heard at the beginning of the new footage which was filmed by specially-trained police officials. It also shows fireworks being repeatedly fired into groups of people with many of them exploding at the feet of the police officers trying to control the 2,000-strong crowd. Revellers pay little or no attention to instructions from police officers who can be heard expressing their frustration at their inability to deal with the mob and one police officer can be heard complaining, 'I'm standing here all by myself'. Police in Cologne this week revealed that 1,500 officers - ten times as many as last year - will be on duty this New Year's Eve to avoid a repetition of last year's events. They are also planning helicopter surveillance of revellers, limiting the number of people in certain areas and deploying police officers trained in investigating sexual assault. VICTIMS DESCRIBE TERRIFYING ORDEAL AT HANDS OF MOB ATTACKERS Since the vast scale of the attacks emerged, several victims have come forward to describe terrifying scenes in the marauding mob. An 18-year-old had an abortion after she was raped in the mass sexual frenzy at Cologne train station on New Year's Eve. She was thrown around a group of men before eventually falling on the floor, where she was raped alongside another girl. Frauke Mahr, 63, who is the manager of the Project for Girls in Cologne, told prosecutors on her behalf: 'She was separated from her girlfriend, and ended up being shoved from one man to another. She was then thrown to the floor and raped. 'She told me that a few metres away she saw another girl lying on the ground, also being raped. 'She had tried to signal to the other girl that she should close her eyes, but the man then grabbed her own head and forced her to look at him.' Her ordeal ended when a policeman pulled the man away and she ran home in a panic. Katja L, 28, said she was with three friends outside the station when they encountered a group of 'foreign-looking men'. 'Suddenly I felt a hand on my bottom, then on my breasts, then I was groped everywhere,' she told Cologne tabloid Express. 'It was horrible. Although we screamed and flailed about, the guys didn't stop. I was beside myself and think that I was touched about 100 times across around 200 metres [220 yards].' A woman in her 30s, interviewed on rolling news channel N24, said she was groped by a group of 'Arab-looking men'. 'They didn't look at me aggressively, they seemed more curious than anything, and a little drunk,' she said. 'I was furious.' According to Bild, a student named Evelyn, 24, from Rheinland-Pfalz, who was at the train station in Cologne, said: 'I had a knee-length skirt on, and suddenly I felt a hand on my backside under my dress. I turned round immediately and saw a grinning face.' She said that she managed to get to the cathedral and sat on a bench and suddenly she was surrounded by men once again, and had only heard them speaking Arabic. 'The only English they knew was "Hey Baby". I was grabbed and held by the arm and it was a nightmare. We were trapped in a mass of people.' Lea Westkamp, 19, told a TV station: 'I was surrounded and helpless. I could do nothing. These men were all over me.' Meanwhile, one teenage victim of last year's sex attacks, who was named only as Lisa S, 18, has spoken publicly about her ordeal for the first time. Lisa, from Bavaria, was on her way to the New Year's Eve celebrations in the city's cathedral square with her two cousins when they were assaulted. She said: 'We were immediately grabbed in our genital area from all sides, my dress was raised. 'My cousin was grabbed by her arm as they tried to pull her away. 'We tried to defend ourselves but we had no chance, as soon as we could escape one of them groping us, we were again groped by others.' After they managed to escape, the three cousins spoke to the first policeman they saw but he told them he was busy and could not help, Lisa said. In total, 1,222 criminal complaints were investigated by the authorities in Cologne, of which 513 involved an accusation of sexual assault. These included sexual coercion, rape and sexually motivated insults. So far only 35 of the accused men have appeared in court with a total of 24 found guilty. Six of the 24 cases are still pending appeals, while 18 sentences have been made final. Of these, just three related to sexual assaults. Cologne was not the only German city were sex attackers escaped from prosecution after out-of-control New Year's celebrations. In Hamburg, 245 investigations into sex attacks resulted in only four accusations and one prosecution, according to prosecutor Nana Frombach. Frombach indicated the number of attacked women was 410 at last year's celebrations in the city. Similar incidents were reported in Frankfurt, Dortmund, Dusseldorf, Stuttgart, and Bielefeld. BOOM IN IMMIGRATION LEADS TO HEIGHTENED TENSIONS Cologne, located in the state of North Rhine-Westphalia, is a 2000-year-old city which was first established as an outpost of the Roman Empire. Throughout the following centuries, its population has steadily increased to now number more than 1million people, with a total of 3million living in the wider area. The huge population boom is attributed to immigration, much of which comes from Turkey. Official statistics show that in 2006, just over 30 percent of the population were migrants and 120,000 were Muslim. However, these figures are likely to have drastically altered in the past two years as waves of migrants from Syria and other conflicts in the Middle East make their way into the country. Last year alone Cologne welcomed 10,000 migrants into the city. The exact numbers of the recent influx have not yet been confirmed by official statisticians, but in 2012 - before the worst of the asylum-seeking crisis had begun - migration flows had already risen by a third from the previous year. This huge migration, which many in Germany fear will over-run existing social systems and infrastructure, has been partly facilitated by Chancellor Angela Merkel's willingness to take in 1million migrants this year alone.