Published: Jul 23, 2012 10:41 PM EDT

CAPE CORAL, Fla. - Cape Coral's city manager offered a detailed explanation Monday, after city staff members were accused of criticizing council members on an open mic.

City manager John Szerlag sent a memo to council members, which he read at Monday night's council meeting, following concerns raised by a city resident and media reports.

"None of the presenters made any comments that would disregard the opinions of the city council, or minimize the seriousness of the UEP," Szerlag said.

The incident happened last Wednesday during a rehearsal for a presentation on the Utility Expansion Project.

Cape resident Ken Zeske raised questions after he heard it on the city's cable channel.

"Some of the remarks I heard were very disrespectful like hearing, if the council knew if these specs existed, we'd be in a lot of trouble, but don't worry, I got them buried in the weeds so far, they wont find them," Zeske said.

Szerlag said the mic only picked up portions of conversations, and some of the alleged comments were misheard.

"The allegations trying to tie this comment to project specs and information being hidden from council is pure fabrication and was never said," Szerlag said.

"I don't see any smoking gun here," said council member Kevin McGrail.

Many of the council members accepted the city manager's explanation; but the mayor-- who was allegedly criticized in the comments-- wasn't satisfied.

"Let's do a real investigation," said Mayor John Sullivan. "I'd like to everyone in that room, including me, Mr. Leetz and Mr. Zeske get on a polygraph machine. Let's really find out what's going on."

Other council members say there's no evidence for an investigation, since there's no recording of the incident.

"(Council staff) was notified by a manager from Comcast, that no recording was available," said council member John Carioscia, Jr.

"Don't know that we need to get into tens of thousands of dollars for an 'oops,'" said council member Chris Chulakes-Leetz.