The NYPD sought the subpoena after Twitter refused to cooperate in a probe of ominous posts that referenced the shooting deaths last month of 12 people last month at a showing of "The Dark Knight Rises" at an Aurora, Colo., movie theater, said NYPD spokesman Paul Browne.
Police received new information from Twitter on Tuesday "that we're using as part of our ongoing investigation," the spokesman said. He offered no further details.
A Twitter spokeswoman declined to comment Tuesday.
Police say the tweets appeared aimed at the audience for "Mike Tyson: Undisputed Truth," the solo show directed by Spike Lee at the Longacre Theater in midtown Manhattan.
"This s--- ain't no joke yo I'm serious people are gonna die just like in aurora," police said one tweet read. Another from the same account warned, "I'm in Florida rite now, but it'll happen i promise I'm just finishing up my hit list."
Before complying with the subpoena, Twitter had told the NYPD in an email, "We appreciate the timeliness and sensitivity of this matter, and have reviewed the reported Twitter account. While we do invoke emergency disclosure procedures when it appears that a threat is present, specific and immediate, this does not appear to fall under those strict parameter as per our policies."
Browne said the NYPD has beefed up security at Longacre as a precaution.
There were police with automatic weapons and specially trained dogs.
Tyson's wife Kiki, who wrote the show, told Eyewitness News that the former champ isn't concerned.
"The police and everyone did their jobs, their due diligence, and handled it and everything's great, so we have no worries," she said.
Some of those waiting for the show Tuesday night were disappointed in the people who run Twitter.
The company refused to identify the person posting the threatening tweets until it was ordered to by the court.
(The Associated Press contributed to this report.)
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