(Reuters) - New York Mayor Michael Bloomberg lashed out on Saturday at the Long Island-based power company that serves some of New York City's outer neighborhoods for making inadequate progress restoring power to thousands of residents in the dark since superstorm Sandy struck on Monday night.

At a press briefing, Bloomberg said the Long Island Power Authority, LIPA, "has not acted aggressively enough" in its power restoration efforts, particularly in bringing electricity back to the Rockaways, a series of beachfront neighborhoods devastated by the storm.

(Reporting By Dan Burns; Editing by Peter Cooney)