An inter-faith organisation in Britain says Muslim communities have been gripped by an endemic sense of fear, since the slaying of a British soldier on the streets of London.
Faith Matters, which runs a helpline, said it had received 162 calls since Wednesday, up from a daily average of six.
Drummer Lee Rigby, 25, was killed near Woolwich Barracks on Wednesday.
Michael Adebolajo, 28, was filmed by a passer-by saying he carried out the attack because British soldiers killed Muslims every day.
He and a second suspect, Michael Adebowale, 22, are in hospital after being shot by police at the scene.
Faith Matters director Fiyaz Mughal said the incidents ranged from attacks against mosques, graffiti, the pulling off of Muslim women's headscarves and more general name calling and abuse.
"What's really concerning is the spread of these incidents. They're coming in from right across the country,'' he told the BBC.
"Secondly, some of them are quite aggressive very focused, very aggressive attacks.''
He also said there also seems to be very significant online activities, suggesting attacks against Muslims and places they congregate are being co-ordinated.