A network of private and public surveillance cameras, license plate readers and weapons sensors already established in Lower Manhattan as an electronic bulwark against terrorist attacks will soon expand to a large patch of Midtown Manhattan, Mayor Michael R. Bloomberg and Police Commissioner Raymond W. Kelly said Sunday as they announced the allocation of $24 million in Homeland Security grants toward the effort.
Mr. Bloomberg said the expanded monitoring network would cover the areas between 30th and 60th Streets, from the Hudson to the East River.
“We cannot afford to be complacent,” he said, noting that Midtown includes landmarks like Grand Central Terminal, the Empire State Building and the United Nations.
Like the system downtown, the expanded surveillance network would feed streams of data for analysis to a coordination center at 55 Broadway. Mr. Bloomberg, who made the announcement at the center with Mr. Kelly, said work on the Midtown system would begin next year and be completed in 2011.
Behind the mayor, a 40-foot video wall displayed maps, incoming data from a police precinct and more than a dozen video streams, many of them showing tourists taking photographs on a sunny day.
The plan devised to protect downtown Manhattan, known as the Lower Manhattan Security Initiative, was introduced by Mr. Kelly in 2005. That raised concern among civil liberties groups, which have called for more public discussion as the police peer, with greater intensity, at more corners of the city.
Asked Sunday about criticism of the increased surveillance, Mr. Bloomberg said: “We live in a world where we have to have a balance. We can’t just say everybody can go everyplace and do anything they want.”
He added, “Do you really want to work in a building that doesn’t have security?”