Attorney General Cuomo is launching an investigation into Facebook Inc., claiming its popular social networking Web site is not as safe from sexual predators as its image and promotional materials suggest.

Mr. Cuomo yesterday announced his office was sending subpoenas to California-based Facebook after a preliminary investigation found the company took little action when alerted to the presence of potential sexual predators, creating an environment that contrasts with the relatively safe appearance the company promotes.

In a letter to Facebook’s owners, Mr. Cuomo wrote that his office “is concerned that in Facebook’s efforts to grow, the company may be giving a lower priority to the safety and welfare of its users, and in particular, underage users.”

While Mr. Cuomo noted the company is legally permitted to operate “any type of website it deems fit,” it “does not have the right to represent that its site is safe and that it promptly responds to complaints when such statements are not accurate.”

Given the widespread prominence of Facebook.com, the investigation could attract much national attention for Mr. Cuomo, who made headlines earlier this year with a probe into the practices of student lenders. Facebook is a giant of the social networking industry, attracting 52 million unique viewers worldwide in June, according to the Internet tracking service comScore. The site was the second-most visited in its category, ranking behind MySpace.

In the letter to Facebook, Mr. Cuomo wrote that his office created numerous undercover profiles on the site, and repeatedly reported sexual solicitations of underage users to the company. A spokeswoman for Facebook, Brandee Barker, said in a statement that the company takes the concerns seriously. “We are committed to working closely with all the state attorneys general to maintain a trusted environment for all Facebook users,” Ms. Barker said.