DUBLIN, Ireland — Charles Haughey, a four-term prime minister whose career was haunted by ethical questions, died Tuesday following a decade-long battle with prostate cancer.

The government ordered flags at half-staff and planned a state funeral Friday for the 80-year-old Haughey, who died inside his mansion north of Dublin with his wife and children by his bedside.

During his political career, Haughey struggled to keep secret the mysterious sources of his wealth.

He solicited more than $10 million from Ireland's top businessmen, a practice later exposed by taxpayer-funded investigations into his implausibly lavish lifestyle.

Haughey tried to stop the probes into his wealth, denied receiving donations until evidence proved he was lying, and never acknowledged granting favors for the cash.

But even Haughey's most ardent detractors conceded Tuesday he was a uniquely charismatic figure with a magnetic lust for life. As leader of Ireland's Fianna Fail party from 1979 to 1992, he became known as "the great survivor" because of his ability to bounce back.