Anger erupted in England after soldier and father Lee Rigby was killed by men claiming to be avenging global violence against muslims. Since then, attacks on mosques and muslim citizens have been reported.
Police are investigating whether anti-Muslim sentiments were behind a fire early Wednesday that left a Somali community center in north London badly damaged.
The fire in the Muswell Hill neighborhood is being treated as suspicious, the Metropolitan Police said.
Police told CNN that one of the lines of inquiry in the investigation is the possibility of an anti-Muslim attack.
Graffiti reading "EDL" -- initials usually used to refer to the English Defence League, a far-right group -- were found on the side of the building, a Met Police statement said. "Officers are investigating any potential connection between the graffiti and the fire."
The force "will work closely with the Somali and Islamic communities to provide support and reassurance," the statement said.
Specialist officers from the Met's Counter Terrorism Command are leading the inquiry.
Emergency services were called to the fire at the Somali Bravanese Welfare Association around 3:20 a.m.
One woman was treated by the London Ambulance Service for injuries not suffered in the fire, police said.
Chief Superintendent Adrian Usher told reporters at the scene that the question of when and where the "EDL" graffiti were placed was a focal point for inquiries.
Community leaders said they and the center had existed peacefully in the neighborhood for the past 20 years, he said.
Police will increase patrols in the area over coming days, he said. There have been no arrests so far.
Community tensions have been heightened in some parts of London since a soldier, Lee Rigby, was killed in an attack in southeast London on May 22. Two men have been charged with his murder.
Additional police have been put on patrol since his killing in Woolwich.
The English Defence League has staged a number of protest marches in London and elsewhere. The group says that Islamic law is poised to overthrow British society and calls for Britons to act aggressively to pre-empt it.
Its symbolism resembles that of neo-fascist groups, and its logo is adorned with red medieval crosses.
Cressida Dick, assistant commissioner for the Metropolitan Police, told lawmakers Tuesday that hate crime reports had spiked after the Woolwich attack but that they now appear to be declining.
There have been some "horrible attacks on mosques," but she was not aware of any assaults on people, she told the House of Commons Home Affairs Committee.
"We will investigate everyone reported to us robustly," Dick said, as well as boosting local policing to reassure Muslim communities.
The spike in reported crimes was less than the one following the 9/11 attacks in the United States and the 2005 bomb attacks on London's transport system, she added.
CNN's Erin McLaughlin and Alexander Felton contributed to this report.