Thieves in Midtown Manhattan hotels have stolen guests’ belongings or swiped hotel property dozens of times this year, law enforcement officials said.

Last month, for example, two guest rooms were broken into at the New York Marriott East Side, on Lexington Avenue, according to a spokeswoman for the New York City Marriott hotels, Kathy Duffy. On August 19, a suspect, Gary DeLeo, was arrested in connection with one of the Marriott burglaries, law enforcement officials said.

There have been at least four thefts this year – three of them last month – at the Roger Smith Hotel, also on Lexington. On August 27, a suspect in one case was arrested. The hotel’s general manager, Phoebe Knowles, said: “It is not a problem that we face normally.”

In Midtown this year, burglaries and grand larcenies – theft of property that among other things can exceed $1,000 – have also been reported at the Benjamin Executive Suite Hotel, three W hotels, the Alex, the Jolly Hotel Madison Towers, 70 Park Avenue Hotel, the Hudson Hotel, the Mandarin Oriental Hotel, the Palace Hotel, and the Crowne Plaza Hotel at United Nations, according to the authorities.

In one precinct alone, Midtown North, at least 18 grand larcenies and burglaries at hotels were recorded between August 8 and September 4, police said. The New York Police Department does not keep citywide statistics for crimes in hotels, and no citywide year-to-year data could be obtained.

In possibly the first hotel theft in Midtown in 2005, on January 3 at 9:52 p.m., a computer was stolen from an office room at the Alex, on East 45th Street, law enforcement officials said. A man, Fernando Castro, 30, was arrested and charged by the district attorney’s office with petty larceny and criminal possession of stolen property in connection with the crime.

The hotel front manager, Ed James, said Mr. Castro was a housekeeper with no prior record. Mr. Castro told his employers he had tossed out the computer, which was in a box, as he threw out the trash, Mr. James said, but “unfortunately the hotel didn’t buy that statement.”

Since the hotel’s opening nearly two years ago, there has not been another theft on premises, Mr. James said. The chairman of the safety and security committee of the Hotel Association of New York City, Jimmy Chin, said more crimes happen to guests once they leave hotels. Taking into account the number of hotel rooms – there are about 66,000 rooms in the 200 association hotels – as well as the city’s low crime rate, Mr. Chin said, the number of thefts is negligible. “I think we’re doing excellent,” he said.