On a day when billions in profits and losses would be determined by split-second trades, the salaried professionals of Japan’s financial markets were glued to their news terminals. Another group was staring at the feed of an anonymous Twitter account.

It was shortly after noon on Jan. 29, 2016, and people with money at stake were waiting for the Bank of Japan to announce its monetary policy. While the decision’s date is set in advance, nobody knows its timing.

“It’s a negative interest rate bazooka!” wrote the Twitter user, who goes by the handle Okasanman. They attached a screenshot of an article just published on a local news website, which showed the BOJ was discussing introducing minus rates as its latest shock-and-awe stimulus weapon.

As stock futures jumped and the yen tumbled, some traders expressed gratitude for the warning. About 15 minutes later, the bank said it was taking borrowing costs below zero.

“This post saved my life,” one user gushed in reply. “The profits I made are thanks to it.”

Okasanman has been dubbed a “locust lord” because the account attracts a swarm of traders who seek to profit from the prolific tweets on everything from global economic data releases to the latest twists in developing political situations. While the account only points to already available information, the speed at which it does — and the breadth of its coverage — has built a following that’s larger than that of the BOJ.

“How is it so fast?” asked Hajime Sakai, chief fund manager at Mito Securities Co. in Tokyo, where he helps oversee $594 million. “I’m very curious to know.”

Okasanman’s identity and motivation for spending hours every day providing information to more than 129,000 followers for free are a mystery. The person or people behind the handle didn’t respond to multiple requests for comment. But the account is another example of how microbloggers — from anonymous short sellers to market commentators such as Zero Hedge — are becoming a feature of how information is transmitted through modern financial markets.

The Okasanman account scavenges through a huge range of sources, at all hours, to find potentially market-moving news. That includes newspapers and magazines, financial data providers, disclosures to the stock exchange, and tweets on accidents or fires. Many appear to be automated, though manually written commentary shows a love of groan-worthy puns and occasionally crude content.

In August, the account was among the first to tweet an exclusive report by a local magazine, not normally known for its market-moving scoops, that pharmaceuticals giant AstraZeneca PLC had made an unsuccessful takeover bid for Japanese drug company Daiichi Sankyo Co. — and that a purchase was still possible. The surge seen in Daiichi Sankyo shares was their largest in nine years.

“His tweets are absolutely crucial,” said Naoki Murakami, a prominent day trader with more than 38,000 followers himself.

On any given day, the tweeting is relentless. On Dec. 20, the account sent 111 tweets, starting at 12:44 a.m. and ending at 11:46 p.m. Cryptocurrencies: 33 tweets. The U.S. Senate vote on the tax bill: 3. Other topics included a disgraced sumo wrestler, a report on North Korean ICBM tests, and the latest Pokemon movie.

Okasanman “must have researched what sources have been fastest over the years” for given topics, said Katsuhiro Yoneshige, founder and chief executive officer of JX Press Corp., which develops apps that source breaking news from social media posts. “It’s probably not something you can build in a day.”

Little is known about Okasanman. There’s the profile picture: a cartoon man in a yellow safety helmet. There’s the profile description. Work: IT-related, investor, day trader. Interests: music (Japanese singers and bands), movies (cult and science fiction), psychology and languages (English and Finnish). “Live market commentary from 12:30 p.m. to 3:10 p.m. every weekday,” it says. “A pretext for a gag-fest.”

And that’s it, apart from the occasional hint among the tweets. Okasanman seems to live in an unfashionable residential area just outside Tokyo and appears to own a cat. But is it a man or woman? And is it run by a single person, or multiple Okasanmen?

“I think he might be a bit older,” says Yoneshige, who at 29 says some of Okasanman’s cultural references are from before his time. The language used, as well as a taste for dad jokes and an obsession with Ivanka Trump, would seem to point to a middle-aged man, but Bloomberg News was unable to speak with anyone who could confirm who Okasanman is. The first autocomplete suggestion in a Google search for Okasanman is “identity.”

The only interaction Bloomberg News was able to secure with him for this article was when it was published. Following its release, he retweeted the story in typical dissembling style. “Even if you follow this account, only your puns will improve,” he joked, referring to his own account.

Okasan Securities Group Inc., a mid-tier Japanese brokerage, says it has nothing to do with the account.

The motives are also unclear: Why go to so much effort to provide the information for free? There seems to be no attempt to monetize the feed, or tweets that might be supplied by sponsors.

Not everyone is that impressed. “I’ve never really imagined what he could be like,” says perhaps Japan’s most-famous tweeting day trader, who goes by the handle Cis. “He tweets news really fast. That’s my only impression.”

But one thing is certain: Okasanman’s influence has grown so much that the account can cause confusion when it indulges in the occasional prank, such as a tweet in November 2016.

“Kuroda to hold emergency press conference on resignation,” it said.

Coming after almost a year of criticism of the Bank of Japan’s negative rate policy, many followers took this to be a reference to BOJ Gov. Haruhiko Kuroda. Two minutes later, Okasanman clarified: It was Hiroki Kuroda, former pitcher for the baseball team Hiroshima Carp.

KEYWORDS BOJ, Twitter, Japan, okasanman