Today’s mystery: Why did Park Slope’s Chamber of Commerce prez resign?

The head of Park Slope’s main merchants group has abruptly resigned — and abandoned his job at a popular gym — leaving behind a fog of speculation and a temporary leadership crisis amongst neighborhood businessfolk.

Jason Daniels — the president of Park Slope Chamber of Commerce — quit last week after less than a year leading the group.

The fitness instructor-turned-businessman did not return several calls and e-mails seeking comment — but the Chamber’s new president, real-estate broker Tammy Shaw, said he resigned due to time restraints.

“He took on more than he could handle,” she said. “He left for the benefit of the Chamber.”

But that hasn’t stopped members of the tight-knit organization from speculating that the former president actually resigned under duress or amid pressure to leave.

Daniels’s Chamber responsibilities included leading monthly meetings, putting on festivals and events and, more recently, organizing a Seventh Avenue Business Improvement District, which would levy a new tax to help clean up Park Slope’s main shopping strip.

As president, Daniels maintained a highly private persona: He rarely responded to calls from the press, has a private number and almost zero presence online.

In September, however, he organized a self-defense class at his gym S-Clubs Fitness on Union Street after a string of attempted rapes in the neighborhood.

Former Chamber president Mitch Szpicek said he had “no idea” why Daniels had quit — but a receptionist at his gym offered a clue, explaining he had ditched his job around the same time.

“Jason?” she said.

“He is no longer with us.”

Reach reporter Natalie O'Neill at [email protected] or by calling her at (718) 260-4505.