Divisional Fire Officer, Tobago, David Thomas, says several people are being interviewed in relation to a fire which destroyed a portion of a commercial building in Goldsborough on Tuesday.
He said the same people are also being interviewed by police in connection with the firebombing of a car in the village of Louis D'Or, that same day.
"The process of the investigation is ongoing," Thomas told Newsday.
"There are several persons to be interviewed and we have our suspicions and we have some evidence leading to it. But we are not in a position to give conclusive statements.
"Out of an abundance of caution, we are doing our due diligence and as soon as we could make a definite statement we will do that. But the process of the investigation is ongoing."
Fire officials responded to call around 2 am on Tuesday in which a portion of a building, owned by Victor Kirk, was gutted by fire. About half and hour later, a car was also firebombed.
The building housed a wholesale business and clothing store, which was partially destroyed. The clothing store was owned by Verna Cornwall-White.
Thomas reiterated damage to the building and its contents has been put at close to $1.5 million.
"The entire store was gutted and that lies on the eastern side of the building complex and that is where housed the clothing store," he said.
Thomas said the suspect/s later set ablaze the car belonging to Eartha White, Cornwall-White's daughter, at Louis D'Or Land Settlement.
Thomas said the fire officials and police are leaving no stone unturned in investigating the incident.
"We are using all of the necessary technology and all of the forensic intelligence to bring this case to closure.
"But, it is an in-depth investigation. So, information would not be readily available in the short term."
Roxborough police are investigating.