Fire services in Northamptonshire saw a small decrease in the number of fires they attended last year, figures from the Home Office show.
In the 12 months to September 2017, the most recent data available, the Northamptonshire Fire and Rescue Service attended a total of 402 house fires, a drop of six per cent on the previous year.
The figure includes 40 cases of arson.
Since 2013, four people have been killed in deliberately-started fires.
In total, 12 people lost their lives in incidents attended by fire services over the past five years.
In the past year alone eight people died, the highest recorded level for five years.
There were also 60 casualties, including 41 people who were taken to hospital as a result of their injuries.
Dave Green, national officer at the Fire Brigades Union, said: “Starting fires deliberately in the home is a heinous crime.
“Rightfully, it is a serious criminal offence punishable by law.
“Arsonists do not just put the immediate victims at risk.
“They put whole communities and firefighters themselves in jeopardy.
“The fire and rescue service is already stretched to the limit in the fire cover they can provide.
“If firefighters are dealing with an arson at the same time as another fire call comes in, then those other victims are looking at a long wait before we can get to them.”
Across England, 346 people lost their lives in fires between October 2016 and September 2017, including 47 in deliberately started fires.
The Grenfell Tower fire in Kensington in June 2017, which claimed 71 lives, meant the figure was the highest for any 12-month period since the data was first recorded in 2009.
There were more than 30,000 house fires across the country over the year, more than 3,000 of which were started deliberately.