The fire last month that ravaged an agency offering charter flights to Cuba from Miami was set deliberately, authorities determined.

According to a Coral Gables Fire Department report, obtained by Miami's El Nuevo Herald newspaper, the blaze that destroyed Airline Brokers Co. before dawn on April 27 was a case of arson.

The owner of the 20-year-old firm, Vivian Mannerud, told investigators that she had received threats and had been the object of hostile activities due to the nature of her clientele, the report said.

Experts found on the floor next to one of the burned walls the remains of a green crystal bottle and an object that appeared to be a piece of cement paving, which could have been used to break the building's windows.

They also found the remains of a disposable lighter and traces of a liquid accelerant, according to the authorities, who up to now have made no arrests nor have they interrogated any suspect.

In the 1970s and '80s there were several attacks in Miami, home to a large Cuban exile community, against travel agencies offering trips to Cuba.

A federal anti-terrorist team and FBI agents continue to investigate the attack against Airline Brokers, which during the recent visit of Pope Benedict XVI to Cuba chartered several additional flights to the island.