WASHINGTON -- Democrat Bob Graham told a Senate colleague Thursday that he would abandon his struggling presidential bid, a Democratic source said, but in a day filled with mixed signals, aides said he will continue to campaign.

The Florida senator's future in the crowded Democratic field remained in doubt as the campaign made several staff changes and held a series of high-level meetings.

Initially, the Graham campaign announced a news conference for today at 2 p.m., suggesting that he would quit the race. But late Thursday, the campaign and state Democratic Party said there would be no news conference. "Senator Graham has decided to soldier on," said Florida Democratic Party chairman Scott Maddox.

A Democratic source, speaking on a condition of anonymity, said the three-term senator had informed one of his colleagues that he was getting out of the race.

Graham spokesman Mo Elleithee disputed the account and said Graham had not talked to anyone in the Senate getting out.

FDA formally approves dirty-bomb antidote

WASHINGTON -- A German company won U.S. approval Thursday of a "dirty bomb" attack antidote -- a compound long used as the artist's pigment Prussian blue.

The Food and Drug Administration had called in January for drug companies to seek permission to manufacture pill forms of Prussian blue, considered for decades a treatment for exposure to certain forms of radioactive cesium and thallium. But until now, national stockpiles of Prussian blue pills have been limited, and bought from overseas.

The FDA's action Thursday clears a German company to sell its version here, with the brand name Radiogardase, potentially making it easier to stockpile more in case of a terrorist attack.

Radioactive cesium and thallium are commonly used, at low doses, in medical treatment and diagnosis. But high levels can be deadly, and they are among the materials that officials worry might be used in a "dirty bomb" -- a device that isn't nuclear but that uses conventional explosives to disperse radioactive material.

Army sergeant on leave wins $150 million jackpot

FITZGERALD, Ga. -- An Army sergeant on leave from South Korea claimed the $150 million jackpot in the multi-state Mega Millions lottery.

Stephen Moore, 30, had been visiting family during his 30-day leave when he bought the winning ticket at a convenience store.

He said he was out with his brother Tuesday night, and when he returned he found his wife, Danielle, waiting for him.

"She came out the door, and I thought I was in trouble," Moore said. "She said, 'Guess what, we won the lottery!"'

Moore, who works as a chemical specialist, chose the cash option for his winnings and was awarded $88.9 million before taxes on Wednesday.

Judge orders injunction to block suicide show

ST. PETERSBURG, Fla. -- A judge Thursday barred a rock band from holding an onstage suicide that its leader vows will occur this weekend during a performance to be broadcast over the Internet.

St. Petersburg city officials had asked Circuit Court Judge John C. Lenderman for the injunction after the group Hell on Earth announced plans to have a terminally ill person commit suicide during a show somewhere in the city Saturday night. The judge had issued a temporary order Monday blocking the performance and any advertising for it.

Hell on Earth leader Billy Tourtelot, who did not attend the hearing, had said earlier the band will defy a city law passed Monday that makes it illegal to conduct a suicide for commercial or entertainment purposes.

Tourtelot told The Associated Press that the suicide is intended to raise awareness of right-to-die issues. He said it "a select few people" will attend the show at an undisclosed site in St. Petersburg, and that it will be shown live on the band's Web site. He has declined to disclose any details about the terminally ill person.

-- From wire reports