Neighbours living near 32 Marbank Way in northeast Calgary are so on edge they keep a bag of important items packed and ready to go in case the house is set on fire again.

The first in a string of arsons began on March 29.

The house was set alight again on April 1, then again on April 5, and most recently on Sunday morning.

"It's just really scary," said Sidney Lee, who lives next door. Part of her backyard fence was damaged in one of the fires.

She says her parents keep the emergency bag because they are concerned there could be another fire and their home could be at risk.

"We have to be prepared and we have to know our safety precautions and procedures, we are just really worried."

No suspect in case

Calgary police believe all instances are related. They are working to narrow down a motive but don't have any suspects identified.

A security camera at a neighbour's home captured someone around the time of the latest fire, but police have yet to identify the person for questioning.

The arsons have investigators baffled.

"I can't say I have seen a location hit four times like this, especially over a short period of time," said Det. Graeme Sloane.

'It's always been a safe community'

He believes the house isn't being attacked at random, but understands why some neighbours are nervous.

"You are always concerned about the fire spreading."

Because of damage from the earlier fires, tenants living in the home were away during the last arson. No one has been hurt.

Still, Lee says it's changed her view of Marlborough, the neighbourhood her family has called home for decades.

"It's always been a safe community … it's just very unsettling because it could spread to our house any time it happens."