The church was completely destroyed by the fire
Police say "nothing has been ruled out" as the cause of a fire which destroyed a former church earmarked for conversion into a mosque in Lincoln.
Muslim leaders in Lincoln said the community was upset by the fire at St Matthew's Church on Boultham Park Road.
Police and fire experts have completed the first stage of their investigation.
Dr Rameez Zafar of the Islamic Association of Lincoln said: "Whether or not we will be able to have a mosque on this site now is not clear."
He said the mosque was needed because the current one was too small to cater for the Muslim community in Lincoln, which includes students at Lincoln University.
Dr Tanweer Ahmed, a trustee of the Islamic Association of Lincoln, said: "It is a real blow to our plans - it is completely shocking news for us.
"We will definitely build a new mosque in Lincoln, but we are not sure where."
The timber and corrugated iron building, which dates from 1912, was severely damaged on Saturday.
The Grade II listed structure had been put on the at-risk register after falling attendances left it neglected.