Fire crews were called to the blaze at the 130-year-old Bethel Community Church in the Stow Hill area of Newport on Friday evening.
According to the BBC, 250 people, including Newport's mayor, gathered for the outdoor service near the destroyed church.
"Our building may be gone, but the church is alive," said Pastor Andrew Cleverly.
Moving service this morning with the congregation of Bethel Community Church. ❤️ pic.twitter.com/cD2wZGKkTU
— Michael Enea (@mikeenea) June 17, 2018
A 43-year-old man and a 36-year-old woman are being questioned in connection with the fire.
Just come back from the moving service in the lower Stow Hill car park. A passionate congregation determined to carry on despite the huge fire that devastated their Bethel Community Church. Lots of others showing their support & offering help. pic.twitter.com/CVoy0MGFKC
— Miqdad Al-Nuaimi (@mndsc06) June 17, 2018
Authorities said the fire started in a disused nightclub attached to the church.
Around 40 residents were evacuated as a precaution, with others urged to keep doors and windows closed, Jennie Griffiths, joint head of South Wales Fire and Rescue Service said.
More than 70 firefighters using 10 fire engines and 11 supporting appliances, including a crane, were needed to bring the blaze under control.
It's emerged that concerns were raised with the local council about the safety of the former nightclub building before the buildings caught fire on Friday.
According to the BBC, Newport Conservatives said they emailed the city council last week calling for the former nightclub space to be inspected due to "fear this could collapse or end up going up in flames".
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