LOS ANGELES (Reuters) - Flying sharks chomping through New York City drew a record audience for Syfy's "Sharknado 2: The Second One," and became the most tweeted-about TV movie on social media, the U.S. cable network said on Thursday.

"Sharknado 2," which aired on Wednesday and reunited leading stars Tara Reid and Ian Ziering from last year's campy hit "Sharknado," drew 3.9 million viewers to become Syfy's most-watched original movie.

The network added that the film also attracted 1.6 million viewers in the 18-49 demographic that advertisers covet.

On Twitter, Syfy, a unit of Comcast Corp's NBCUniversal, said "Sharknado 2" garnered 1 billion impressions across conversations on the micro-blogging site, and was also among the top trending topics of Wednesday evening.

In the movie, an aerial shark attack causes large-scale destruction across Manhattan. It features numerous cameos including "Today" show hosts Matt Lauer and Al Roker and country music singer Billy Ray Cyrus.

Last year's "Sharknado" became a surprise hit for U.S. cable channel Syfy after attracting a cult audience drawn to the film's low-budget special effects about a hurricane that unleashes hungry sharks on Los Angeles.

The popularity of "Sharknado," which drew an audience of 1.4 million with its July TV premiere last year, created a social media frenzy that drew larger audiences to rebroadcasts of the film, and led the network to release "Sharknado" in 200 U.S. movie theaters.

Syfy is continuing the shark attacks with "Sharknado 3," due out in summer 2015.