Downtown St. Thomas was hit by two major fires in less than 24 hours on the same block, the most recent starting early Thursday morning.

Three businesses were destroyed, including the city's only methadone clinic.

Fire crews were called to Big John's Plumbing at 5 New Street around 4 a.m.,  just a couple of hours after extinguishing a blaze at a vacant building next door that started Wednesday evening. That building was supposed to be demolished in two days,

The owner of the plumbing store had gone to his shop to check on it after Wednesday night’s fire.

“He had a candle going in the building that fell over and started the fire,” says Bill Todd of the St. Thomas fire department.

An auto parts store was also destroyed.

For some residents, it was hard to believe.

“It was quite a shock to find out about it. To see the fire last night and then to be told again that it re-started and everything was up in flames again,” says Harley Perry, who owns a lot beside the destroyed buildings.

Residents gathered and watched as fire crews put out the flames and demolished the remains.

“I drove around behind it and there's a smell of smoke in my vehicle now, which is pretty crazy,” says Tim Vyse.

Staff at the methadone clinic, which served about 400 patients, wanted CTV News to mention that a shuttle will be offered to take clients to see a doctor who could write prescriptions.

“It's really sad. This will affect a lot of people. We'll rebuild. We have to look after a lot of people,” says the clinic’s Debbie Saddler.

St. Thomas Mayor Heather Jackson is upset to lose a significant area of the city.

“It was devastating news for the community, for the downtown. We've essentially lost an entire block.”

She remains thankful that there were no serious injuries and is looking ahead to picking up the pieces.

“It opens up a whole corner of possibilities and how the re-development can look.”

The investigation of both fires is complete and no charges will be laid.