Ipswich mayor Paul Pisasale has resigned dressed in hospital pyjamas 24 hours after Crime and Corruption Commission detectives searched his council office and home.
A subdued Mr Pisasale stood before reporters at St Andrew's Ipswich Private Hospital to announce he was resigning because of a worsening of his well-known battle with multiple sclerosis.
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Pisasale retires from Ipswich Council
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"It's a very sad day for me and a very emotional day," Mr Pisasale said.
"My journey has been going for 26 years and I am so proud to have been the mayor for such a wonderful city," he said, wearing a white hospital gown and red pyjama pants dotted with white stars.
Mr Pisasale became an Ipswich councillor in 1991 and was elected mayor in 2004.
Known as "Mr Ipswich" because of his high media profile, Mr Pisasale was due to travel to New York on Sunday to attend the week-long World Intelligent Communities Forum, but changed his plans, the city's acting mayor Paul Tully said on Tuesday.
"Paul was due to be in New York, to have left yesterday, for a summit with the World Intelligent Communities Forum, where there is an announcement being made on Thursday," Cr Tully said.
"He cancelled that conference at the weekend.
Cr Tully told reporters that Crime and Corruption Commission detectives searched Cr Pisasale's council office on Monday with a warrant.
"I can confirm that," he said.
Asked if police officers also searched Mr Pisasale's house, he said: "I think so."
The CCC released a statement within hours of Mr Pisasale's announcement confirming it had executed a search warrant at Ipswich City Council on Monday.
"The search was related to an ongoing CCC investigation," the commission said.
"As the investigation is ongoing, it is not appropriate for the CCC to comment further."
Mr Pisasale said he would co-operate with any CCC inquiry.
"As you know, I have co-operated wholeheartedly with them and I intend to continue to do so," he said.
He declined to comment on actions the CCC may take on Tuesday afternoon.
"I'll wait and see what that says," he said.
Cr Tully asked people not to speculate until the facts were presented.
"I am not aware there are any allegations against the mayor," Cr Tully said. "It's a fact-finding information exercise at the moment."
Cr Tully said Tuesday's events would come as a shock to the people of Ipswich.
"All the councillors came up to see him this morning," he said.
"And there were tears in the eyes of just about every other councillor."
Mr Pisasale said he was extremely proud of the way the city had transformed.
"I love this city, I think it is the most wonderful city in the world," he said.
"Now is my time to look after my health and for the last 48 hours the staff here have been fantastic."
Mr Pisasale recently fronted a Crime and Corruption Commission hearing as part of the watchdog's investigation into the Ipswich, Gold Coast and Moreton Bay council elections.
This probe has since been expanded to the Logan council election.
As Mr Pisasale's resignation came within the first three years of his current term, a byelection to replace him must be held.
A spokeswoman for Local Government Minister Jackie Trad said that byelection would have to be held before August 29, within 12 weeks of Mr Pisasale's resignation.
The timing of that byelection would be a matter for the Electoral Commission of Queensland, she said.
Comment has been sought from the ECQ.
Brisbane Lord Mayor Graham Quirk on Tuesday paid tribute to Mr Pisasale for his advocacy of Ipswich.
"He was a colourful character, unconventional in many ways and he performed his duties for many years while suffering from multiple sclerosis.
"I could always detect when Mayor Pisasale was having a bad day with that, but he continued on.
"But regardless of what news might emerge, I just want to thank him for his advocacy for Ipswich."
- with Mark Solomons, Cameron Atfield and Ruth McCosker