A rise in the number of hate crimes against Muslims in London is being encouraged by mainstream politicians and sections of the media, a study written by a former Scotland Yard counter-terrorism officer, published yesterday, says.

Attacks ranging from death threats and murder to persistent low-level assaults, such as spitting and name-calling, are in part whipped up by extremists and sections of mainstream society, the study says.

The document – from the University of Exeter's European Muslim research centre – was written by Dr Jonathan Githens-Mazer and former special branch detective Dr Robert Lambert.

"The report provides prima facie and empirical evidence to demonstrate that assailants of Muslims are invariably motivated by a negative view of Muslims they have acquired from either mainstream or extremist nationalist reports or commentaries in the media," it says.

Lambert headed Scotland Yard's Muslim contact unit, which helped improve relations between the police and Britain's Islamic communities.

The unit won praise from even long-standing critics of the police, and Lambert was awarded an MBE.

The study mentions no newspapers or writers by name, but alleges that the book Londonistan, by the Mail writer Melanie Phillips, played a part in triggering hate crimes.

"Islamophobic, negative and unwarranted portrayals of Muslim London as Londonistan and Muslim Londoners as terrorists, sympathisers and subversives in sections of the media appear to provide the motivation for a significant number of anti-Muslim hate crimes," it says.

In his foreword, the rightwing journalist Peter Oborne writes: "The constant assault on Muslims from certain politicians, and above all in the mainstream media, has created an atmosphere where hate crimes, ranging from casual abuse to arson and even murder, are bound to occur and are even in a sense encouraged by mainstream society."

The report is based on interviews with witnesses to and victims of hate crimes, as well as police officers and former members of extremist organisations such as the British National Party.

The report cites interviews with rightwing extremists to try to prove a link between what is published in the mainstream media and the anti-Muslim views held by extremists.

It says: "An experienced BNP activist in London explains that he believes that most BNP supporters simply followed the lead set by their favourite tabloid commentators that they read every day.

"When these commentators singled out Muslims as threats to security and social cohesion, he says that it was perfectly natural for BNP supporters to adopt the same thinking."

The report says the extreme right are directing their violence more against Muslims than black or Asian Britons.

"Interviewees with long experience of extremist nationalist street violence in London are unequivocal in their assessment that Muslim Londoners are now a prime target for serious violence and intimidation in the way that Londoners from minority ethnic communities once were," it says.

"Similarly, interviewees with experience of London street gangs that have no connection or affinity with extremist nationalist politics are adamant that Muslims have become prime targets for serious attacks.

"In addition, well-informed interviewees are clear that the main perpetrators of low-level anti-Muslim hate crimes are not gangs but rather simply individuals from a wide range of backgrounds who feel licensed to abuse, assault and intimidate Muslims in terms that mirror elements of mainstream media and political comment that became commonplace during the last decade."

The report says the attacks come in part from street gangs targeting Muslims as punishment for members who have embraced Islam and left gang culture.

"Often, they know someone who has left their scene and become a devout Muslim," the document, which also drew on interviews with youth workers dealing with gangs, says.

"That is like a defection. And whether they do or don't, they say they know this or that terrorist who used to be a great person till he joined the Muslims."

The report also says gang members believe Muslims values "oppose everything these kids aspire to. Flash cars, nightclubs, expensive clothes, jewellery, drugs, alcohol, casual sex, glamour, dancing, music ...".

The study says the majority of hate crimes involve low-level incidentsand are not reported to police.

Most officers are committed to tackling anti-Muslim hate crimes seriously, but are undermined by a few colleagues who are not. But the study warns: "Anti-Muslim hate crimes have not been afforded the same priority attention [that] government and police have invested in racist hate crimes."

The report is dedicated to Yasir Abdelmouttalib, a PhD student who was left brain-damaged after a gang of youths attacked him in London, striking him over the head with a stick, as he made his way to a mosque while wearing Islamic clothing.

It cites other cases of rightwing extremists preparing hate campaigns and of serious attacks on Muslims in Britain.

These included: "Neil Lewington, a violent extremist nationalist convicted in July 2009 of a bomb plot; Terence Gavan, a violent extremist nationalist convicted in January 2010 of manufacturing nail bombs and other explosives, firearms and weapons; a gang attack in November 2009 on Muslim students at City University; the murder in September 2009 of Muslim pensioner, Ikram Syed ul-Haq; a serious assault in August 2007 on the Imam at London Central Mosque; and an arson attack in June 2009 on Greenwich Islamic Centre."

The study focuses on anti-Muslim violence in London, with its authors saying they will produce one covering the whole of the UK by this summer.