A blaze last month that scorched the offices of a Cuba travel agency in Miami was deliberately set, fire investigators say, one of the first acts of violence in years against a company arranging visits to the island.

The Coral Gables Fire Department said in a report that investigators found a disposable lighter, the remains of a green bottle, and a piece of asphalt after the April 27 fire at the Airline Brokers Co.

Those items indicate the "potential use of a projectile to breach the building window, and the use of a liquid accelerant incendiary device in this fire," the report says.

The report was obtained by the Spanish-language newspaper El Nuevo Herald, which published a copy on its website. Coral Gables fire officials referred all inquiries to the state fire marshal's office, which did not return requests for comment by phone or e-mail Sunday.

The blaze severely damaged the offices of the company, which arranged the flights and travel for hundreds of Cuban-Americans and others to the island for Pope Benedict XVI's visit in March. The agency has also recently expanded its operations to include flights from Fort Lauderdale.

In the 1970s and `80s, bombings of businesses and Cuba travel companies considered sympathetic to the Castro regime were commonplace. Another uptick of violence occurred in the summer of 1996, when Marazul Charters, a company that arranges legal flights to the island, had two of its offices bombed. A second travel business, Maira and Family Services, had a bomb thrown inside its offices within the same month.

But in the last decade, such incidents have become unheard of and travel to the island has grown. President Barack Obama removed a cap that limited family visits soon after taking office. Last year, the Cuban government said it was expecting 500,000 U.S. visitors annually, most of them Cuban-Americans, many of whom still have strong ties and family on the island.

"It surprised me," said Maira Gonzalez, whose former business was targeted more than a decade ago. "I thought people had matured a bit."

Gonzalez said her company went out of business about a year after someone threw what she described as a Molotov cocktail inside their offices early one morning. No one was in the building. Police said gas spilled but the device did not go off.

The incident scared off customers and business declined.

"We thought we were helping the Cuban community, but there are always others who think differently," Gonzalez said.

The report on the Airline Brokers Co. fire noted that the business owner said she had been the subject of threats and other hostile activities in the past. But Vivian Mannerud told El Nuevo Herald she had not received any recent threats, even as they were arranging flights for the papal visit.

No possible suspects have been identified.