Rob Ford, the combative former mayor of Toronto who gained international notoriety with his confession of crack cocaine use, his public drunkenness and his belligerent clashes with other public officials, died on Tuesday. He was 46.

His office announced his death but gave no other details. Mr. Ford had been undergoing treatment for malignant liposarcoma, a rare form of cancer, since September 2014.

Along with his brother Doug, Mr. Ford was a controversial figure in Toronto politics for years, drawing support largely from conservative residents of suburban communities that had been absorbed into the City of Toronto. In 2013 he acknowledged smoking crack cocaine during one of his “drunken stupors,” as he put it.

After his cancer diagnosis, Mr. Ford withdrew from his mayoral re-election campaign in favor of his brother, who was defeated. But Rob Ford did win the seat on the City Council that Doug Ford had held.