NEW YORK (CBSNewYork/AP) — A group of New York elected officials, community activists and housing advocates gathered on the steps of City Hall Friday to launch a campaign against the home-sharing company Airbnb.

Airbnb matches homeowners and travelers, providing a lodging alternative to hotels. Opponents say it is hurting the hotel industry and landlords and inconveniencing other apartment building tenants.

The anti-Airbnb group called itself Share Better. It was joined by elected officials that included Public Advocate Letitia James, State Sen. Adriano Espaillat (D-Manhattan) and Manhattan Borough President Gale Brewer.

“Airbnb, according to the attorney general, has almost 16,000 units in the City of New York,” Brewer said.

The group says many hosts who live in rent-controlled apartments are breaking the law and State Sen. Brad Hoylman said unscrupulous landlords are turning affordable housing units into illegal hotels, WCBS 880’s Monica Miller reported.

“Now we all are in favor of the share economy, but what about the fair economy,” ge said,

They’re asking city lawmakers to impose tougher fines on people who illegally rent their apartments and add resources to the city’s Office of Special Enforcement.

In response to the group’s concerns, Mayor Bill de Blasio said a crackdown on illegal Airbnb participants is under way.

“We have been increasing enforcement, and you’ll see more enforcement as we go along. There’s different types of realities, obviously, under the rubric of Airbnb and the sharing economy, obviously, and some of them are things to embrace, and some are examples where some individuals get outside the law – and we’re obviously going to follow up on that very aggressively.”

The mayor said policies are also needed to deal with issues of technology and commerce.

Airbnb denies doing anything illegal and is conducting its own ad campaign touting its benefits. The company says it housed more than 400,000 visitors to New York last year.

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