Mohamed Seineldin, a former army colonel who led failed military uprisings against two elected governments seeking to prosecute dictatorship-era human rights abuses in Argentina, died Wednesday. He was 75.

Friend and family spokesman Gustavo Breide Obeid said Seineldin suffered a heart attack in his office in Buenos Aires and later died in a hospital.

Seineldin, a nationalist who gained fame for his role in Argentina's 1982 Falklands War against Britain, was an ideologue of the "carapintada," or "painted face," movement - soldiers who rebelled against the governments of President Raul Alfonsin and President Carlos Menem in the late 1980s and early 1990s.

The carapintadas demanded that the government end legal proceedings against lower-ranking officers accused of involvement in the kidnapping, torturing and killing of dissidents during Argentina's 1976-83 military dictatorship.

Seineldin led military rebellions against Alfonsin in 1988 and two years later against Menem's administration. The second rebellion resulted in 14 deaths, including five civilians.

The ex-colonel was sentenced to life in prison, but was pardoned in 2003 by then President Eduardo Duhalde.