Campaign trail tensions erupted when top officials from Mayor Thomas Menino's administration this week crashed a Mattapan forum hosted by mayoral hopeful and City Councillor At-Large Sam Yoon.

During the 90-minute forum held at Foley Senior Residences, Yoon criticized the city's Elderly Commission, calling it a political arm of the Menino administration. Yoon pointed to literature and handbags the commission hands out that prominently bear Menino's name, along with the city seal.

"It almost exists to serve the mayor," Yoon said in front of a small crowd of 60 people, many of them seniors. "Elders deserve better than that."

Mayoral candidate Sam Yoon discusses issues with a supporter.

The comments outraged Judith Kurland, Menino's chief of staff, who attended the forum, along with Larry Mayes, the city's chief of human services, and James Hills, special assistant to the mayor.

"I take personal offense," Kurland cut in, calling the remarks "disingenuous."

Kurland, who at one point was shouted down by the Yoon-friendly crowd, pointed to Menino's high approval ratings among seniors. "It's because he's done so much," she said. "It's not because of electioneering."

As she spoke, Jim Spencer, a top Yoon strategist who was standing next to Kurland, asked where the mayor was. (Menino, at the time of the Tuesday night forum, was at Tia's, a Boston waterfront restaurant that was hosting an "evening of conversation" with Young Professionals for Menino.)

"He's in Mattapan often," Kurland snapped back.

The Mattapan forum, organized by the Yoon campaign, was the first in a series of planned "town hall" meetings.

Tempers flared again later in the forum when Larry Ellison, president of the Massachusetts Association of Minority Law Enforcement Officers, said Menino had "not considered" a person of color for the job of police commissioner. He added that Menino did not include people of color in his administration. Ellison was echoing a criticism that has also come from the Bay State Banner, a local weekly that focuses on the black community.

Mayes, who was seated in the audience, broke in: "I'm in the mayor's cabinet. I'm a person of color."

Speaking to the Reporter after the forum, Mayes also pointed to Sandra Henriquez, whom the Obama administration recently poached for a slot in the U.S. Department of Housing and Urban Development. She had served as head of the Boston Housing Authority since 1996.

"Boston is not just black and white," Mayes said, adding that diversity extends to Hispanics, Asians, and sexual orientation. "The bench has to be open to everybody."

Mayes added that Menino had done a "fair job" when it comes to appointing people of color. "Could there be more? Absolutely," he said. "And the mayor is not satisfied. He wants to see more."

At the end of the forum, Kurland offered to meet with attendees to counter "a little bit of misinformation."She was shouted down by the crowd's cries of "where's the mayor?"then yelled back: "How often have you seen Councilor Yoon in Mattapan?"

During the forum, Yoon kept up his criticisms of the longtime incumbent who is also facing challenges from City Councillor At-Large Michael Flaherty and South End businessman Kevin McCrea.

Fifty-five of the city's schools -- a third -- are labeled underperforming, Yoon said, arguing that the city's school committee needs to move back to being elected, in part, instead of appointed and under control of the mayor. Yoon proposes a hybrid model of appointed and elected members.

Yoon has also said the city's school drop-out rate has remained high throughout Menino's tenure.

Kurland pointed to a front page story in the Boston Globe on Tuesday that said 78 percent of the city's 3,300 high school graduates in 2007 had enrolled at two- and four-year colleges.

Yoon also slammed the mayor's budget process, saying that there was a lack of transparency while Yoon, a Fields Corner resident, was holding community forums. Yoon has charged that there were savings to be made through the removal of the city's antiquated fire boxes and the elimination of the Boston Redevelopment Authority.

Kurland said the $2.4 billion budget is available on the city's website and three months of public hearings are held. "It's all public," she said.

"Some councillors attended the budget hearings and some don't," she said in a shot at Yoon's attendance record. "That's all I'll say on that."

CORRECTION: A correction has been appended to this article. Councillor At-Large Yoon supports moving the school committee, whose members are appointed by the mayor, to a hybrid model where some are elected and some are appointed.