After two vehicles cut off Cardoso's car, two unidentified assassins opened fire with AK-47 assault rifles, killing him instantly and seriously wounding his driver, according to local and international news reports.
The Mozambican government quickly condemned Cardoso's assassination and promised to carry out a full investigation.
Cardoso, 48, was an experienced investigative journalist who had become one of Mozambique's foremost media personalities. He was internationally acclaimed for his groundbreaking reporting on political corruption and organized crime in Mozambique, a country that is still recovering from a brutal, 17-year civil war.
Earlier in his career, Cardoso served as editor and later director of the Mozambique state news agency AIM, from which he resigned in 1989. Before founding Metical in 1998, Cardoso ran another independent fax newsletter, Mediafax, which he launched in 1992. He sympathized politically with the ruling FRELIMO party but often lambasted the government in his editorials.
One week before his death, Cardoso started a campaign against what he called the "gangster faction" in FRELIMO, which he accused of provoking recent political violence in the country. Metical had also been reporting aggressively on alleged wrongdoing at the Mozambique Commercial Bank (BCM), according to the London-based anti-censorship organization ARTICLE 19.
On the day of Cardoso's assassination, unknown attackers slashed the tongue of Radio Mozambique journalist Custadio Rafael for "speaking too much," according to news reports. Rafael had also been investigating the BCM scandal.
Local human rights groups, government officials, and opposition leaders all condemned the killing. Outside Mozambique, the U.S. State Department, the European Union, and several African nations denounced Cardoso's murder as a serious setback to press freedom in Mozambique.
On November 24, a group of 500 outraged local journalists and citizens marched from the headquarters of the Mozambican Journalists Union in downtown Maputo to the site of Cardoso's assassination in the suburb of Polana.
In March 2001, Mozambican authroities arrested Momade Abdul Satar, his brother Ayob Abdul Satar, and Vincente Ramaya, a local bank official, and charged them with ordering Cardoso's murder. Police also arrested three young men from the Maputo underworld alleged to have carried out the assassination. Both the Satars and Ramaya were involved in a money laundering scandal at BCM dating back to 1996, which Metical covered aggressively. Authorities said the Satars and their accomplices killed Cardoso because of Metical's coverage of that banking fraud.