NEW YORK, July 3 (Xinhua) -- New York City will beef up security on Thursday for the annual Fourth of July fireworks show, among other celebrations, according to authorities.

The New York Police Department (NYPD) will deploy thousands of uniformed and plainclothes officers to safeguard millions of people who are expected to line the East River to watch the fireworks display, with blocker vehicles stopped at key intersections, police officials said on Tuesday.

Though there's no specific, credible threats to the city at the moment, Police Commissioner James O'Neill told New Yorkers to stay vigilant while enjoying the festivity.

"If something doesn't look right, if it doesn't feel right, call 911, or tell a cop," said the commissioner at a press briefing on late Tuesday.

Police will also have canines, helicopters and surveillance cameras at hand to detect anything suspicious, and a drone will be used to watch the crowd from above, according to officials.

Thursday's annual Macy's Independence Day fireworks show will take place just south of the iconic Brooklyn Bridge. Street closures around the area will begin at 2 p.m. (1800 GMT) and public viewing areas will be opened at 6 p.m. (2200 GMT) on Thursday, according to officials.

All bags brought into the viewing area are subject to security checks. Prohibited items, such as lawn chairs, large coolers and umbrellas, will be taken away, said James Waters, chief of NYPD Counterterrorism Bureau.

The bureau has started conducting sweeps of the city's waterways in preparation for the show, Waters said on Twitter on Wednesday.

Macy's fireworks show is the largest Independence Day fireworks display in the United States, and has become a major attraction for millions of spectators on site and more in front of TV since its inauguration in 1976.