The chairman of the Portland Downtown District is asking businesses to provide temporary shelter to the organization’s summer guides after “a few incidents” of guides being accosted or feeling threatened by street people, according to an email sent out Monday.

One guide quit the job, according to the email from the nonprofit group, which is made up of businesses tasked with maintaining a clean and safe downtown.

The email was signed by Michael Mastronardi, chairman of the Portland Downtown District, who is also serving as the interim executive director while Steve Hewins is out on medical leave. Mastronardi declined to comment on the email to businesses, saying he first wanted to speak with the district’s directors.

According to the email, the Portland Downtown District has reported the incidents to police and is asking businesses to post “welcome” signs in windows to alert guides that it’s safe to shelter. The email does not provide details of the alleged incidents. However, it also warns businesses about “the return visit from last year’s camouflaged group of aggressive beggars and thieves.”

Portland police could not immediately identify reports regarding the incidents mentioned in the email. Police Chief Michael Sauschuck was out of the office and did not return calls.

The summer guides are stationed in and around the Old Port to direct tourists and answer questions. Three summer tour guides wearing bright orange T-shirts stationed at a Portland Downtown District kiosk in Tommy’s Park on Monday afternoon said they were asked not to comment to a reporter.

City councilors, including David Marshall and Kevin Donoghue, who represent the downtown, and Ed Suslovic, who chairs the public safety committee, said they were not aware of any increase in aggressive panhandling. Trish McAllister, a city attorney who has dealt with panhandling cases in the past, had also not heard about the complaints.

“I haven’t gotten any complaints yet,” said Marshall, who serves on the downtown district’s board but missed the last meeting.

Suslovic said he fielded complaints last year about unruliness downtown, which was attributed not only to panhandlers, but also street artists.

He said the downtown district’s alert is “cause for concern” and plans to add the aggressive panhandling issue to the committee’s July agenda, which also includes graffiti and motorcycle noise.

“It’s very important we maintain an atmosphere downtown where everyone feels welcome and everyone feels safe,” Suslovic said.

The Portland Downtown District has been less visible in City Hall in recent months, Suslovic said. He said he hopes it reached out to Portland police before alerting its members. “We all need to be working together on this,” he said.

Mark Swann, director of Preble Street, a nonprofit social services agency that serves the city’s homeless, said he also had not heard of the problems referred to in the email.

“It’s really too bad PDD didn’t reach out to us, perhaps we could’ve helped,” he said in an email. In past summers, he said, Preble Street’s outreach teams have helped to respond to incidents and to train the summer guides.

Swann also disagreed with some language in the email. “The ‘camouflaged group of aggressive beggars and thieves’ characterization seems over the top and insensitive,” he said.

Staff Writer Randy Billings contributed to this report.