Cairo (CNN) It was still dark when Rasha Tarek saw her husband Salah for the last time.

Salah woke up at dawn on March 24 to go to an affluent neighborhood of the Egyptian capital for a painting job, his wife told CNN.

He was due to travel to Upper Egypt after that.

But Tarek suspected that her husband was being unfaithful to her, so she sent her brother, father and a family friend to tag along.

She spoke with her husband while he and the others were en route to their destination. But by 8 a.m. he stopped answering her calls. She tried the others but was unsuccessful in reaching them.

It took almost an hour before someone answered her husband's phone.

Saad Tarek answered a call from his sister as her husband was being killed, she believes

"I heard a noise that I couldn't understand. So I thought it was a network problem. I waited and heard my brother Saad saying, 'Yes, basha. Why are you upset, basha? Just tell me what you want. I swear to God, I'll do what you want, basha,'" she said.

"Basha" is customarily used to address people of higher status, especially the police.

Tarek never saw her husband, father or brother alive again. She thinks her brother answered the phone as they were being killed by Egyptian security forces.

"What I didn't realize then was that the noise I was hearing was the sound of my husband dying," Tarek said.

Salah Ali, Saad Tarek, Tarek Abdel Fattah and Mostafa Bakr -- Rasha's husband, brother, father and family friend, respectively -- were killed that morning, along with another man that the police didn't immediately identify.

It later turned out to be the driver of their vehicle, Ibrahim Farouk, according to his family.

Egypt's Interior Ministry said in an official statement that the men were outlaws, killed in a shootout with the police

Italian student mystery

The deaths might have attracted little attention outside the men's families, but officials quickly linked them to the killing of a young Italian man in Cairo two months earlier.

Giulio Regeni, a Cambridge University graduate student, disappeared in Cairo on January 25. His battered and bruised body was found in early February

The incident would spark outrage in Italy, where officials question the various explanations Egypt has offered for young man's death.

Police said they found Giulio Regeni's passport at the home of Rasha Tarek's aunt.

One official explanation involves the family of Rasha Tarek.

After the shooting of Tarek's husband and others, seven weeks after Regeni's death, authorities said the men were involved in the student's killing.

Police said they had extensive criminal records and specialized in kidnapping and mugging foreigners, impersonating policemen to do so.

Regeni's passport, credit card and university ID were found at the apartment of Rasha Tarek's aunt, Egyptian police said, along with a bundle of stolen wallets, sunglasses and phones in a red bag bearing the Italian flag. The bag also contained fake police IDs, officials said.

Tarek and other relatives of the dead men contend they had nothing to do with Regeni's disappearance. She says she believes authorities planted Regeni's passport at her aunt's home.

And she found the claims of kidnapping foreigners absurd: Her father and brother couldn't read or write, much less speak another language to communicate with foreigners, she said.

How did Giulio Regeni die?

Regeni, 28, had gone to Cairo to conduct research on Egyptian trade unions for his doctorate at Cambridge, according to friends and colleagues.

He disappeared while en route to a birthday party on January 25, the fifth anniversary of the start of the uprising that ended the reign of President Hosni Mubarak.

Giulio Regeni was buried in his native Italy on Feb. 12.

Police were deployed by the thousands to the streets that day to prevent any demonstrations.

Regeni's body was found nine days later on the western outskirts of the capital, with the corpse bearing signs of "inhumane, animal-like violence," according to the Italian interior minister.

There is currently no official Egyptian statement about the cause of Regeni's death. But over time, authorities and local media have presented several different scenarios.

The day Regeni's body was found, the police official who now leads the investigation said it was a car accident.

The first prosecutor assigned to the case rejected that explanation immediately.

Regeni's family denies that the student was a spy.

Journalists and other observers questioned whether Egyptian security was involved.

But Egyptian Interior Minister Magdy Abdel-Ghaffar said Regeni was never detained by the police.

Later, the independent daily Al-Wafd quoted an unnamed security source claiming the Italian was a spy working for the UK.

His family rejects that, denying that Regeni ever worked with or for any intelligence agency.

Shootout, or something else?

Rasha Tarek concedes that her husband, father and family friend had criminal records.

That made them easy targets for the police, she believes.

They had been convicted of impersonating a police official, she admits, but says that is because they found a wallet containing a police ID. She says they never used it, but were charged with the crime when police caught them with it at a checkpoint. Her husband and the family friend, Bakr, also had drug possession convictions, she said.

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And regardless of their pasts, they did not deserve their fate, Tarek said.

"Even if they broke into a checkpoint and did something wrong, who gave you the right to execute them this way?" she asked. "Their entire bodies looked as if they were used for shooting practice."

The Interior Ministry said the men were killed in a shootout as they fired at the police at a checkpoint in El-Tagamou El-Khames, the eastern suburb of Cairo dotted with villas and gated compounds.

Local media published what they said were pictures of the dead men and the vehicle. One shows two bloodied men seated inside a microbus with a pool of blood on the seats.

Another shows the vehicle's bullet-riddled windshield.

But no photos have been released showing the weapons used or the damage to police vehicles described in official statements.

Tarek's family said their kin were not armed.

Murky details, grisly deaths

One high-ranking government official who spoke to CNN suggested there might not have been a shootout per se.

But, the official said, they probably "didn't stop and drew their weapon(s). Police don't have to wait for the criminals to shoot. They have to act and shoot at them. Whoever shoots first will kill the other."

He refused to give the full details of the alleged confrontation or its exact time.

Killed by police Tarek Saad Abdel Fattah, Rasha Tarek's father Saad Tarek, her brother Salah Ali, her husband Mostafa Bakr, a family friend Ibrahim Farouk, driver

The prosecution is no more forthcoming about that part of the investigation.

The lack of information has left Tarek with many questions, including whether the men were trying to escape from police.

"If they ran from you, you'd have shot the back of the vehicle, not its front. You could have shot at the tires. You could have shot the driver, so he would stop or the car crashes -- if they resisted and fired at you, as you claim," Tarek said, speaking rhetorically of the authorities.

Only Sameh, Tarek's 21-year-old brother, was allowed to see the bodies at the morgue. He said he fainted as soon as he stepped out. He said most of them had bullet wounds in their ankles. His father had two bullets that went through his head and abdomen. His brother had a bullet wound in the head.

"Salah, my brother-in-law, took a bullet that split this part," he said, pointing to the left side of his head. "It was the same for the driver, half of his face was split off," Sameh said. This is consistent with the account given by the driver's family of what they saw in the morgue.

CNN couldn't obtain the official autopsy report. The family's lawyer said it was difficult to obtain any documents, including the men's criminal records, since the case is handled by the National Security Agency.

Questions about the evidence

Two days after the men were gunned down, Egyptian police downgraded the alleged level of involvement of Tarek's family in the Regeni case.

"There is nothing in our statements that tie the five to the murder of the Italian man. We only found a new variable in our investigations," Interior Ministry spokesman Abu Bakr Abdel-Karim told local TV stations after the Italian student's belongings were allegedly found at the home of Rasha Tarek's aunt.

The aunt, her husband and Tarek's mother and uncle were arrested on the same day. Their lawyer and relatives say they remain in detention. They have not yet been charged with a crime.

After Regeni's body was found, there was a memorial for him outside Italy's embassy in Cairo.

Tarek says she can explain most of the items allegedly found in the apartment.

On her mobile phone, Tarek went through pictures. She pointed to a wallet emblazoned with the word "Love" and said it is her mother's.

The sunglasses belonged to her younger brother Sameh. The phone and headphones belonged to her late brother Saad, she said. The red bag is also theirs.

A brown wallet, she said, belonged to her late husband. It was on him, she said, when he left on March 24.

"I was surprised that it was with the other things. This proved to me that the police officer is the one who brought (Regeni's belongings) with him," when they searched the apartment, Tarek said.

Egypt's Interior Ministry has not responded to CNN questions about Tarek's accusations.

International outrage

Long before Rasha Tarek and other family members of the dead men spoke up and challenged the police story, Italian investigators dismissed the idea that those men kidnapped and killed Regeni.

Speaking to the Italian news agency ANSA, they said torture of the victim isn't consistent with criminals looking for a ransom; a gang wouldn't keep compromising evidence; and, "It is not credible that an entire gang of alleged kidnappers was killed by police, thereby preventing any possibility of getting corroborating statements from any of them."

"The story is too convenient for the government. It's too good to be true," said Mohamed Lotfy, executive director of the Egyptian Commission for Rights and Freedoms.

The deaths of the five is the latest twist in a complicated tale that put Cairo in the crosshairs of Italy, the United Kingdom and the European Parliament.

Regeni's parents call accounts of the alleged shootout the "umpteenth attempt at a cover-up on the part of the Egyptian authorities." Many observers say the kidnapping scenario is implausible.

Critics demand to know whether Egypt is doing its best to investigate his death -- and whether its much-criticized security forces themselves are responsible.

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Egyptian authorities up to and including the nation's President deny that.

President Abdel Fattah el-Sisi said security forces were not involved. He contends that "evil" Egyptians and social media users made up the claim to make the Egyptian government look bad.

But Egypt's contention that authorities were conducting a transparent investigation has done little to mollify critics.

While Egypt backtracked on much of its story about the men's alleged involvement in the killing, that has done nothing to dampen what has become a diplomatic crisis.

"The responses from Egypt have been insufficient and contradictory and with the clear intent to waste time," Pier Ferdinando Casini, the chair of the Italian Senate's foreign affairs committee, said last month.

And the British Foreign Office also called for a "full and transparent investigation" into Regeni's death, saying it had raised the case with Egyptian officials in London and Cairo.

"We are very concerned by reports that Mr. Regeni had been subjected to torture," the Foreign Office said in a statement.

Diplomatic row persists

Italy's dissatisfaction with Egypt's investigation has built over more than two months.

Rome recalled its ambassador to Cairo in early April after a meeting between Egyptian and Italian investigators reached a deadlock.

Egypt refused to give Italian officials phone records in the areas where Regeni lived and where his body was found, saying it was an invasion of privacy and unconstitutional.

In March, the European Parliament cited the Regeni killing in a resolution critical of Egypt's human rights record.

Egypt rejected that.

"The inclusion of the murder of [Regeni] as part of a resolution addressing human rights in Egypt carries unacceptable insinuations and preempts ongoing investigations," the Egyptian Foreign Ministry said in response to what it described as an "unfair resolution."

But Regeni is not the only person to disappear in Egypt and turn out to have been the victim of violence.

Lotfy, of the Egyptian Commission for Rights and Freedoms, points to 544 cases of disappearances his organization documented in the past eight months. Many of the missing reappeared in prisons bearing torture marks, he said. Others were found dead.

Egyptian authorities not only killed Rasha Tarek's husband, but defamed his memory, she charges.

Egyptian security agencies have "a long track record of violations similar to what happened to Regeni," Lotfy said.

The El-Nadim Center for Rehabilitation of Victims of Violence, an Egyptian rights group, documented 328 killings by police in 2015, including 175 labeled as "liquidation."

Authorities often use this term to describe the killing of suspects during raids or confrontations with police.

A mother of three living in the densely populated, lower-income El-Marg neighborhood, Tarek hadn't heard of Regeni until her family was connected to his case. She hopes that the attention given to his abduction and slaying will mean that she will eventually see justice.

Tarek fears arrest and is staying away from her home. She is angry but remains composed, only breaking down in tears when she recalls the moment she found out about the death of her loved ones and how her son was taunted in school afterward.

"Other kids tell him, 'Your father is a killer. Your father was a con man.' His father wasn't like this," she said, "Not only did they kill them, but they defamed them and made their children's lives impossible."