Damage following a fire at a home in Mount Brydges, Ont. is seen on Friday, Jan. 10, 2020. (Sean Irvine / CTV London)

A fire in a multi-unit century home in Mount Brydges has caused in excess of $500,000 in damage.

The blaze broke shortly before 6 p.m. on Adelaide Road, one of the main thoroughfares in the Middlesex County village.

Strathroy-Caradoc Fire Chief Brian George says all occupants in the duplex were unharmed.

A friend says two of the tenants noticed the start of the fire just as they were returning home. The other tenants responded to smoke alarms, according to George.

Unfortunately, a dog died in the basement of one of the units.

A police cruiser was guarding the scene Friday morning, as the Ontario Fire Marshal’s Office began an investigation at 11 a.m. to determine the cause.

Strathroy-Caradoc police are assisting with the investigation.

It was a challenging blaze to fight, George says, as it spread quickly, “The fire got into the walls and went straight up. It did breach the roof and went from side-to-side within the building.”

One bright spot in the aftemath of the blaze was the return of a family pet.

CTV News noted social media posts saying a black and white kitten named Calu had gone missing during the fire.

While filming at the scene, Calu was spotted and CTV News notified a friend of a young couple impacted by the blaze.

With the assistance of a neighbour the cat is now back with the couple.