Prison staff who were supposed to be guarding notorious Mexican cartel leader El Chapo were all taken off duty during the precise window of time in which he made his daring escape, MailOnline has learned.

Seven prison officials have been arrested over the allegations that Joaquin 'El Chapo' Guzman, leader of the powerful Sinaloa cartel, had help from inside the Altiplano prison to pull off his dramatic escape last Saturday.

The seven have been taken to a federal detention centre.

Prosecutors have held a total of 22 prison officials, including the facility's director, since Sunday for questioning over the arrest.

But relatives of those being questioned insist that the corruption stems from the government, but that the 'poor and humble' people are being forced to pay.

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On the run : The most recent image of Joaquin 'El Chapo' Guzman before he escaped from Altiplano prison

Elaborate: This is the 50cm-by-50cm hole at the base of El Chapo's shower that he used to enter tunnels

Rage: Relatives of some of the prison staff being held are angry that they have been implicated, and claim they are suspicious of why their loved ones were forced to work as guards that day

Family members have claimed that their loved ones are being treated brutally by officials at the detention centre.

They reported bizarre shift patterns within the prison that have been so far unexplained.

Anita Moreno Flores, 30, from Toluca, was ordered to sit in the canteen for an hour between eight and 9pm last Saturday.

Just nine minutes before, at 8.51pm, El Chapo had made his getaway through a hole in the shower floor - although it wouldn't be reported for another half an hour.

Somewhat coincidentally, this was also the first guard shift Ms Flores had ever done: she and others from the prison's administrative office, where she usually works, were told they had to work the evening shift that morning.

Her husband Gustavo Valdez told MailOnline: ‘My wife works in an office doing paperwork for the prison’s administration.

‘But last Saturday morning she and all her co-workers were ordered to go on guard duty. It makes no sense.

‘She and all the other guards were sent to eat in the staff canteen at eight o’clock and were kept there until 9pm,'

Ms Flores is now among the prison staff who have been held through six days of intense interrogation.

‘They complained of beatings they had received from the police when the human rights staff weren’t looking,' one person claimed.

Getaway vehicle: The motorbike that El Chapo used to escape from the maximum-security prison on Saturday

Why?: Edith Mojicka says it can't be a coincidence that El Chapo escaped the same day changes were made

Hurt: Some relatives have claimed the federal attorneys have been 'brutal' towards prison staff

In that time, Mr Valdez has been allowed just 10 supervised minutes with his wife, who had appeared to him in handcuffs and was allowed no physical contact.

‘It can’t be a coincidence that El Chapo escaped the same day these strange things were going on,' said Edith Mojicka, the wife of Anita’s office manager Gerardo Gonzalez, who was also placed on guard duty and sent to the canteen before El Chapo’s 8:51pm escape.

'IT'S WORTH THE WAIT': EL CHAPO SENDS ANOTHER BOASTFUL TWEET Emma Coronel, El Chapo's 25-year-old girlfriend El Chapo has continued to boast of his astonishing escape over Twitter. ‘Today is one of those days on which I can say, "it was worth the wait",' he gloated over Twitter in what many believe is a reference to a long-awaited reencounter with his 25-year-old beauty queen wife Emma Coronel, whose whereabouts is uncertain. Coronel, an heiress to the formidable Coronel crime family, was last seen when El Chapo was recaptured in February of last year, and has been named a ‘top surveillance target’ by the Mexican authorities. Advertisement

Wailing and praying outside the Federal Attorney’s offices, Mrs Mojicka screamed accusations of corruption at the government employees who came to and from the guarded building.

‘They’re the corrupt ones, but the poor and humble people are being forced to pay,' she shouted.

‘This is the way it has always been in Mexico.'

Mexico’s president is facing a public relations nightmare as he confronts fallout from the escape of the notorious drug lord.

President Enrique Pena Nieto famously said following El Chapo's recapture last year that it would be 'unforgiveable' if he escaped again.

This is El Chapo's second jail break in 14 years. The government highlighted his re-arrest in February last year as its biggest victory yet in the war on drugs, since coming to power in 2012.

Pena Nieto was flying to France when news broke that Guzman had escaped, but rather than return home, he continued with the five-day visit.

He said that El Chapo’s escape has ‘caused frustration and fury across broad sectors of society’.

He added: ‘I am sure and I am fully confident that, with the valour, courage and determination of our armed forces and federal security forces… we will again recapture him.’

Seven of the 22 total prison employees detained for questioning have now been formally charged with conspiracy to aid organised crime.

Among their number is believed to be Valentin Cardenas Lerma, the prison director who ordered that the guards be taken off duty during the hour designated for El Chapo’s escape.

Meanwhile, the corruptibility of the prison guards has come into question.

The Altiplano prison staff were forced to take a pay cut less than a year ago and now earn ‘only slightly more than the minimum wage’, according to Ms Flores’s brother-in-law, Felipe Valdez.

‘The pay cut nearly cut their wages almost in half,' he told MailOnline.

The minimum wage in Mexico is 70 pesos (£2.80) per day and, according to Mr Valdez, his sister-in-law ‘wasn’t earning more than 120 pesos’ for the long hours she would work at the maximum-security penitentiary.

‘My husband works extremely hard for very little money,' said Mrs Mojicka. ‘People were constantly being sacked from the prison staff for no good reason and that puts pressure on you to do what your superiors tell you.

‘There’s no doubt that some of the prison employees have accepted bribes’, she said. ‘The question simply is who.'

Given such low wages, it’s not hard for many Mexicans to believe that the staff at the maximum-security penitentiary were corruptible, particularly when faced with the alternatives of cartel pressure.

‘Of course the staff in the prison are corruptible,' Mr Valdez told MailOnline.

‘If I was working in those conditions and then a powerful criminal offered me the choice between $500,000 for keeping my mouth shut or my entire family being murdered for standing up to him then I’d go along with it.'

Allegations that Guzman must have had help from inside the prison to pull off the dramatic escape were made when it emerged that it took 18 minutes for guards to notice he was missing.

CCTV footage released by the government this week showed that Guzman paced in his cell before bending down behind a short partition wall in the shower and disappearing.

He had climbed through a 50cm by 50cm hole in the shower floor, before climbing down a 32ft shaft and into the 0.9mile-long tunnel, which was fitted with a motorcycle.

A poll in the Reforma newspaper said 88 per cent of Mexicans believe the escape was an inside job, and 65 per cent blame the authorities’ incompetence more than the ingenuity of the drug lord.

Some Mexicans say the government should have agreed to U.S. requests to extradite Guzman, on the grounds that U.S. prisons are more difficult to escape from.

The Altiplano prison, just 50 miles outside of Mexico City, is supposed to be the country's tightest-security prison.