Police have launched an investigation after anti-Islamic graffiti was sprayed on a mosque and a vehicle in Bolton, Greater Manchester.
Police said they were called to reports of slogans reading "Islam = Evil" and "Terrorist inside".
The graffiti has been cleaned off the mosque.
Greater Manchester Police have appealed for information and witnesses amd called the act abhorrent. They believe the suspect lives locally.
Supt Steve Nibole said: "Any acts of criminality which are motivated by religious hostility or racism are totally abhorrent and we take action against anyone found to be committing such offences.
"We have launched an investigation and we will do whatever we can to find those responsible and bring them to justice.
"Neighbourhood officers will continue to work very closely with local mosques and partners over the coming days and weeks, both to offer reassurance and advice on taking the appropriate safety measures."
GMP were forced to deny earlier false reports that hundreds of Muslims were "celebrating" and "cheering" on a street in Oldham following news of the murder.
The vandalism is the latest anti-Islamic attack to have occurred since a soldier was murdered in Woolwich, southeast London.
Far-right group the English Defence League clashed with police as they staged a protest against the killing. Around 100 supporters clashed with officers and thew bottles after a rallying cry by the group's leader Tommy Robinson.
In Essex, a 43-year-old man was arrested on suspicion of attempted arson and possession of an offensive weapon.
He was arrested outside the prayer centre in Braintree following reports of an "attack" at a mosque.
In Kent, police were called to reports of criminal damage at a mosque in Gillingham. A spokesman said a man was in custody on suspicion of racially-aggravated criminal damage.
Azeem Nader, general secretary of the mosque, said the man smashed a window and a bookcase which held copies of the Koran.