Colombo: The wife of Sri Lankan ex-army chief Sarath Fonseka accused the government on Tuesday of abducting her husband and treating him "like an animal" following his dramatic arrest.

"This is not an arrest. It is an abduction," a tearful Anoma Fonseka said at a press conference at her Colombo home.

Fonseka, who lost his challenge for the presidency in a January 26 election, was arrested Monday night by military police who stormed the offices of the opposition alliance which had backed his candidacy.

Anoma Fonseka complained that her 59-year-old husband had been "dragged out and treated like an animal" by the soldiers.

"I don't know where he's being held. I don't know his condition. He needs regular medication.

"We always knew that the government will try to arrest my husband, but we never thought they would do it in such a disgusting manner," she said through sobs.

"Is this the gratitude for a general who ended terrorism?"

Fonseka was hailed as a national hero after he led security forces in crushing separatist Tamil Tiger fighters in May last year, ending the rebels' 37-year-old campaign for an independent Tamil homeland.

She said the authorities had yet to formally inform her of her husband's arrest, and voiced concern over whether he was receiving medication he needs after surviving a suicide bomb attack in April 2006.

"Please help me. I need to know where he is so that I can at least give him his medicine. He has already missed last night's dose. What I want to tell the government is: 'Just be reasonable. Treat him like a human being.'"

She accused the government of carrying out a vendetta against her husband for daring to challenge his former commander in chief, President Mahinda Rajapakse, in the January poll.

"They are accusing him of trying to stage a coup on the day of the election," she said. "Our two children and I were with him on that day. There was no coup. This is nonsense."

Fonseka has accused the government of rigging the election and has vowed to challenge the result in the Supreme Court. He has just one more week to file the relevant legal papers.

Opposition politician Rauf Hakeen, who was with Fonseka when he was taken into custody, said the military action was "undignified" and he felt ashamed.

"The way the troops spoke to General Fonseka and the way they forcibly dragged him away is a disgrace to the security forces," Hakeem told AFP. "It is a shameful way to treat your former commander."