Mayor Donald Frush, whose unexplained absence has been a source of concern and curiosity this week, is under a doctor's care for stress and fatigue, his political aides said today.

In a brief prepared statement, Frush's reelection campaign committee announced that the Hagerstown mayor's condition is a result of "his duties as mayor, the campaign, and the aggravation from [a] tooth and gum infection." The information, they said, was based on conversations the mayor had with his brother and one member of the committee.

The statement shed no light, however, on the mayor's whereabouts and left open the question of whether Frush, a Republican, will continue to run in the March 26 municipal election against Democratic challenger Steve Sager.

"Even without [Frush], the campaign can proceed on course because his four-year record speaks for itself," the committee statement said. " . . . It may take several weeks for Don to be in a position to return to his vigorous schedule. It seems that active campaigning, which requires numerous hours of discussing issues with voters, is just about out of the question . . . . The final decision is his."

Frush has not been seen at City Hall since Feb. 25. He last called his office Friday at the end of what was to have been his four-day convalescence following oral surgery. On Monday, Winnie Nolte, a friend of the Frush family, called city officials to cancel the mayor's appointments indefinitely -- and speculation about Hagerstown's "missing mayor" began.

Today, City Hall workers and campaign aides were besieged with telephone calls from reporters from Atlanta to New York wanting to know where Frush had gone. And townspeople traded the latest rumors about their mayor -- among them that he was aboard his cabin cruiser in Annapolis and that he had really been at his home.

"It's just amazing," said Hazel Carpenter, a Hagerstown General Store clerk. "Everybody wants to know what's going on and nobody knows."

Because Hagerstown has a full-time city administrator, Community Relations Director Judy Chambers said, Frush's absence has had little effect on the town's day-to-day operation.

The recent news has been at odds with Frush's reputation as a reliable, if fiercely opinionated, leader.

During recent weeks, however, his behavior reportedly has been erratic. The Feb. 25 issue of the Daily Mail, Hagerstown's afternoon newspaper, reported that at a candidate's forum, Frush gave a 20-minute rambling speech and said, in part, "There's all kinds of rumors out there that I'm drinking too much. I'm at the end of the tube. Somebody's created rumors, but I don't mind. I love everybody."

The newspaper reported that Frush also gave an impassioned speech about the two times he sent his "heart up the flagpole" for Hagerstown -- once, in his unsuccessful attempt to make the strawberry the town's official symbol and again to give the town an official hymn.

The events were also recounted by city residents who were present at the gathering.

This afternoon, after hearing of the campaign committee statement, Sager said, "I wish the mayor a speedy recovery and I welcome him back to the campaign trail." Earlier in the day, however, the 31-year-old real estate developer had talked about the difficulties of campaigning against an absent opponent.

"When I entered the race in October, the consensus would have been that I was a long shot," he said. "Three weeks ago, people were calling it a horse race, dead even. Two weeks ago, after the candidates' forum, I was told it went from a horse race to a clear lead for me."