Argentine lawmaker seeks U.S. help in prosecutor death probe

Argentine prosecutor Alberto Nisman's shooting death came as he was moving forward with damning allegations against President Cristina Fernandez. Now, there are growing calls for an international investigation into his mysterious death one Argentine congresswoman is looking to the United States for help, reports CBS News correspondent Manuel Bojoroquez.

As a stunned nation watches, investigators appear no closer to determining whether Nisman killed himself or was murdered. The special prosecutor died before alleging a coverup that reached all the way to the presidential palace.

The car bomb attack that destroyed a Jewish community center in 1994, killing 85 and injuring 300, remains the deadliest terror attack in Argentina's history.

Sergio Burstein lost Rita Worona, the mother of his two sons in the attack. He's haunted by memories of pulling bodies from the rubble.

Burstein said it feels like it was yesterday and it's made worse that facts about the incident are still not known.

Now, the man who worked more than a decade to find those responsible is dead, too.

Nisman was found in his Buenos Aires apartment with a bullet to his head two weeks ago. Few believe it was suicide, even though President Fernandez originally suggested it was.

Only days later, she blamed the death on rogue intelligence officials looking to frame her. Either way, protestors claim the government isn't telling the truth.

Nisman died the day before formally accusing the president's government of shielding Iranian agents from blame in the attack in a deal for oil. Fernandez denies the claims.

Argentine congresswoman Patricia Bullrich spoke to Nisman the day before he died, but said he never told her about specific threats.

"He said to me he was afraid for ... two daughters. He received a lot of threats," Bullrich said.

She wants the FBI to assist in the probe of Nisman's death. She believes everyone has a stake in getting to the truth.

Investigators say key security cameras at Nisman's apartment building were not working the night he died. The nation is also turning its attention to the political fight over Fernandez's request to dissolve Argentina's spy agency and start a new one.