Attackers tried to set fire to an Essex mosque in a suspected Islamophobic attack.
The Harlow Islamic centre in Paringdon Road was targeted with industrial foam which was then set alight, said police. No serious damage was inflicted on the building aside from burn marks on a wall.
Police are investigating CCTV footage for clues. Around 2,000 Muslims in the Essex town of Harlow use the centre, which has been in the area for 18 years.
Leading the investigation is Ch Insp Ed Wells, who branded the incident "appalling."
"Detectives are investigating this concerning incident and there will be a significant police presence throughout the day to reassure all local residents as we seek to identify those responsible," he said.
"Naturally, if and when we identify suitable, productive footage, we will release this in order to help with our investigation."
"We stand here together today appalled at the criminal behaviour of the individuals who last night tried to set fire to this building."
The vice chairman of centre said efforts had been made to strengthen ties. Zia Rehman said: "We have been working very hard within the local community, building bridges, and we were hoping we wouldn't have this kind of problem, but in the current climate there are elements within society that are not happy and there are issues."