Egypt’s Muslim Brotherhood has rejected a timetable for elections proposed by interim leader Adly Mansour. The plan calls for a parliamentary vote in six months after amendments to the constitution are approved in a referendum.

Essam el-Erian, deputy head of the Brotherhood's Freedom and Justice Party, said that the plan would bring Egypt back to “square one.”

The decree has allowed a four-and-a-half month period for any amendments to the former constitution, which was suspended after the overthrow of the country’s former president, Mohammed Morsi, amid mass protests. 

A presidential election will be held after the new legislative chamber’s first meeting. 

The text of Mansour’s decree states that a panel for the review of the new constitution must be formed within 15 days. 

In the run-up to parliamentary elections, the document also gives the interim president powers to issue new laws after consulting with the new government, which is to be formed soon. 

Certain controversial Islamist-influenced articles of the previous constitution have been left in the decree. They have to do with the principles of the Sharia law. This has already aroused criticism from Egypt’s liberal and Christian populations. 

The developments took place as investigations got underway into violent clashes between the country’s armed forces and the supporters of the former Islamist president earlier in the day. The violence took place outside the Republican Guard headquarters in the Nasr City district of Cairo, claiming at least 51 lives and injuring more than 430 people, according to the Ministry of Health. 

Egyptian supporters of the Muslim Brotherhood rallying in support of deposed president Mohamed Morsi clash with police outside the elite Republican Guards base in Cairo early on July 8, 2013. (AFP Photo / Mahmoud Khaled)

How the clashes started exactly remains a topic of dispute, with eyewitnesses saying that they were fired on and the army insisting they were provoked.   

Adly Mansour has expressed grief at the deaths and has called for calm and restraint. 

UN Secretary-General Ban Ki-Moon has condemned the reported killing of over 50 anti-Morsi protesters in Cairo, urging both sides to “do everything to avoid further escalation” of violence which has intensified since the former president’s ouster.  

Ban’s spokesman issued a statement, saying the UN chief is “deeply disturbed” by the bloody clashes outside the capital’s Republican Guard headquarters early on Monday. He has offered his condolences to the families of the victims.

“The Secretary-General condemns these killings and calls for them to be thoroughly investigated by independent and competent national bodies, and those responsible need to be brought to justice,” read the statement.

A variety of weapons, including gun ammo and Molotov cocktails, were discovered at the scene, near the Republican Guard headquarters in the Nasr City district of Cairo. 

Military spokesman Ahmed Aly spoke at a press conference on Monday, saying that armed groups had attacked the Republican Guard at dawn – not the other way around. According to him, there is much evidence to support this:

"A colleague is in Maadi hospital undergoing a four-hour surgery; he was shot with live ammunition to the head, which caused his skull to fracture," said Aly, who stressed the officer's injury proves that there was firing from building rooftops. 

People run for cover as security forces fire tear gas after shooting to disperse Islamist supporters of ousted president Mohamed Morsi outside the Republican Guard headquarters in Cairo in the early hours of July 8, 2013. (AFP Photo / Mahmoud Khaled)

Aly went on to criticize internet footage of children allegedly being killed in the late hours of the day.

"Religious groups spread pictures showing children [killed]...how children could have been involved in that hour of the night," he said, adding that the pictures being circulated are actually from March 2011.

Aly also underlined the position that that all Egyptians involved in the clashes are “brothers” and that“we call on them to remain peaceful… no one will be hunted down and there will be no extraordinary measures taken.”

Political analyst Hussein Haredy advances the view that the military is hardly to blame for what went down on Monday. He expanded on this view to RT:

“I believe the Muslim Brotherhood is following a scorched-earth scenario in Egypt. They want to set the country on fire; they want to make divisions within the Egyptian military. And they said they are not going to budge until the former president returns to the presidential palace, which is next to impossible in this country.” 

Finally, Haredy believes that had the army not intervened, we would be seeing plenty more confrontations and violence taking place. “I personally believe the army, on July 3, saved this country from a bloody civil war,” Haredy concluded. 

Following the deadly clashes Egypt's Muslim Brotherhood called for more protests on Tuesday and an uprising against those who try to “steal the revolution with tanks”, Reuters quoted the organization as saying. 

It asked "the international community and international groups and all the free people of the world to intervene to stop further massacres ... and prevent a new Syria in the Arab world." 

Meanwhile, Cairo’s Rabaa al-Adawiya mosque became the scene of the third day of protests, as it was swarmed by tens of thousands of Morsi supporters. 

Mohammed Morsi was Egypt’s first recently democratically-elected president. He was ousted less than a week ago after mass protests led to his removal by the military. He had lasted just one year in power. 

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