Police took a 25-year-old man into custody at a car wash in Deception Bay on Friday afternoon following investigations into the suspicious fire.
He was taken to Princess Alexandra Hospital, where he is being treated for injuries allegedly sustained during the arson attack and remains under police guard.
An employee and a customer were inside the targeted shop at the time of the alleged attack but were able to escape unharmed.
Neighbouring business owners said this was not the first time the shop had been targeted.
A worker at a nearby shop rushed to the scene after hearing shouting and a loud bang and, together with a cleaner, used fire extinguishers to stop the blaze from spreading.
Sign up to Herald Premium Editor’s Picks, delivered straight to your inbox every Friday. Editor-in-Chief Murray Kirkness picks the week’s best features, interviews and investigations. Sign up for Herald Premium here.