MADISON, Wis. -- Dane County officials planned to offer apologies to the family of a slain University of Wisconsin-Madison student after revelations last week that a 911 call from the victim's phone was apparently mishandled.

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On Monday, Dane County Board of Supervisors Chairman Scott McDonell said he believes a mistake was made at the 911 Center and apologized. Dane County Executive Kathleen Falk has also drafted some letters of apology to Brittany Zimmermann's family and fiancé, according to a spokesman.

The apologies follow last week's news that the Dane County 911 Center received a call from 21-year-old Zimmermann's cell phone on the day she was killed in early April. However, a 911 dispatcher hung up on the call after apparently hearing nothing and then failed to call back, which violates 911 protocols. Police officers were never sent to investigate.

The news touched off a public round of fingerpointing between Madison police and various local and county officials about whether there was enough information from the call to prompt police to respond.

According to Falk's spokesman, Falk says in the letter that she believes a dispatcher should have called back after hanging up on her to take other emergency calls.

In addition to the apology, Falk is expected to offer a set of directives to the 911 Center director that involve steps that she feels need to be taken so as to prevent similar incidents from happening again.

County leaders said that an internal investigation into the call will be done very soon. They said that Joe Norwick, the 911 Center director, will have the report on Thursday to give to a county committee.

Meanwhile, McDonell said that he's concerned about the number of unsolved homicides in Madison.

"What's going on downtown is something that is disturbing," he said. "I don't think the community has ever seen anything like this."

Officials said that the dispatcher, who has since been transferred to another county job, got busy with other calls and forgot to call the number back.

McDonell said that the mistake shouldn't have happened.

"The county made a mistake in not calling that number back. I think clearly that we did not follow our procedures and I apologize for that. I think it's important that we make sure this doesn't happen in the future," he said.

He vowed to review 911 procedures and staffing as well as a 2004 audit of the center that four years ago warned of dire consequences if changes weren't made in staffing, funding, oversight and other issues at the center.

Norwick met with McDonnell and Falk on what details about the controversial call could be released, without jeopardizing the police investigation or possible prosecution.

County officials cited the ongoing investigation as the reason they didn't reveal the existence of the 911 call or the subsequent investigation into it -- not even to the 911 Center's oversight board.

Bob Salov, a member of the Public Safety Communications Board, said that after the Zimmermann incident, Norwick canceled the board's April meeting, but he isn't sure why.

"It's hard for me to conjecture what the reasoning would be. All I can say is we usually meet regularly. Usually, something of this magnitude would be brought our attention," Salov said.

Norwick declined to comment on Monday and a Falk spokesman said that the county executive didn't notify the board because she was told by police not to say anything about the call.

Norwick is scheduled to meet with a joint Finance and Public Protection and Judiciary committee meeting on Thursday to review policy and presumably the incident, WISC-TV reported.

Authorities said that the search for Zimmermann's killer is continuing. The student was found inside her West Doty Street apartment on April 2. Police said the UW-Madison junior was killed after her assailant broke into her first-floor apartment. Zimmermann's fiancé later found the woman's body in the two-flat house that they shared. Police said that the fiancé isn't considered a suspect.

During this weekend's Mifflin Street Block Party, friends and relatives of Zimmermann were selling food and collecting donations for a memorial fund in the student's honor.

To donate, send money to:

Dollars for Brittany
c/o Marshfield Medical Center Credit Union
P.O. box 279
Marshfield, WI 54449

Stay tuned to WISC-TV and Channel 3000 for continuing coverage.