At least 40 people were hurt when a passenger train rammed a locomotive on a busy stretch of track on the outskirts of Buenos Aires on Sunday, Argentine officials said.

Ambulance and fire crews raced to the crash site south of the capital and dozens of passengers were transported to nearby hospitals, though none were badly injured.

Five Argentine guards were sentenced to life in prison Friday for beating to death an inmate after a trial that exposed the use of torture in the country's crowded jails, a humanitarian organization said.

The beating death of 26-year-old Patricio Barros Cisneros in 2012 brought to light the prison problems in the province of Buenos Aires and led to the guards' convictions.

An Argentine prosecutor on Monday again rejected a case against President Cristina Kirchner for allegedly protecting Iranian officials accused of orchestrating a deadly 1994 bombing.

Prosecutors had been seeking to relaunch the case that was being brought by their late colleague Alberto Nisman, who died mysteriously on January 18 as he prepared to publicly accuse Kirchner of shielding high-ranking Iranians suspected of ordering the attack on a Buenos Aires Jewish center.

Only the DNA of an Argentine prosecutor who died of a bullet to the head was on the gun that killed him, an investigator said Friday, reinforcing initial findings that it was likely suicide.

Alberto Nisman, 51, was found dead in the early hours of January 19 in his Buenos Aires apartment, the same day he was to testify that President Cristina Kirchner had obstructed the investigation into Iranian officials implicated in a 1994 bombing in the capital that killed 85.

The Argentine prosecutor whose sudden death has set off a crisis for President Cristina Kirchner no longer trusted even his bodyguards at the end of his life, an assistant said Wednesday.

A tense Diego Lagomarsino, his voice breaking at times, recounted at a news conference here how he came to give Alberto Nisman the .22-caliber revolver used to put a bullet through his head.

A top aide to President Cristina Kirchner offered assurances Monday that journalists enjoy "full security" in Argentina after a reporter who revealed the suspicious death of a key prosecutor fled to Israel.

Damian Pachter left Argentina on Saturday, saying he had received threats and was followed after being the first to report the sudden death of prosecutor Alberto Nisman.

Argentina's Jewish community pressed for "truth and justice" Wednesday, rallying at the site of a 1994 bombing in the wake of the suspicious death of the prosecutor investigating the attack.

Alberto Nisman was found dead of a gunshot to the head in his home Sunday, the day before he was to go before a congressional hearing to accuse President Cristina Kirchner of a cover-up.

Foreign Minister Jebran Bassil stressed that Lebanon is not involved in any form of terrorism, refusing any links between any Lebanese or a group with any terror act that happened in the world.

Bassil, who is currently in the Argentine capital Buenos Aires on an official visit, told reporters that “Lebanon rejects any form of terrorism,” considering it as a victim of terror.

Pope Francis called Friday for justice to be done in the unsolved bombing at a Jewish center in Argentina that killed 85 people and wounded 300 others two decades ago.

"Twenty years on from the tragedy at the Argentine Jewish Charities Federation (AMIA), I want to express my closeness with the Argentine Jewish community and all the victims' families, whether Jewish or Christian," the pope said in a recorded message played at commemorations of the anniversary.

An Argentine court Thursday declared unconstitutional an agreement with Iran to probe the 1994 bombing of a Buenos Aires Jewish center, with a final decision left to the Supreme Court.

The government, which vowed to appeal, holds that Tehran was behind the attack on the Argentine Jewish Charities Federation, or AMIA, that left 85 people dead and 300 others injured two decades ago.