Hundreds of supporters of ousted president Mohamed Morsi clashed late Monday afternoon with anti-Morsi protesters who have been holding a sit-in in Tahrir Square. Other clashes also erupted in the Qaliubiya province just north of Cairo, and Damietta East north of Nile Delta.

Khaled El-Khatib, head of the central administration for urgent surgery, said three were killed and 40 injured in the clashes that took place in the three cities, according to state news agency MENA.

Mohamed Sultan, the head of Egypt's Emergency Medical Services, announced that 21 people were injured in the clashes in Tahrir. Most of the injuries were caused by gunshots.

A doctor at the Mounira Hospital, a public hospital near Tahrir, confirmed to ONTV that the hospital received one fatality.

The clashes started when pro-Morsi demonstrators approached Tahrir Square on their route to hold a protest rally at the US embassy a few blocks away.

Pro and anti Morsi forces exchanged rocks at some point as well as gunshots.

An army officer told an Ahram Online reporter at the scene that Tahrir campers charged in the direction of the Islamists, believing that the pro-Morsi march, which was headed towards the US embassy, intended to storm the square.

A video published on El-Badil website showed several unidentified men stationed near Qasr Nil Bridge shooting shotguns at protesters in Tahrir Square.

However, Hossam Bakir, the El-Badil journalist who was covering the pro-Morsi march and shot the video, told ONTV satellite station that while the Brotherhood side of the clashes began shooting gunshots the Tahrir side responded with its own.

Shortly after the clashes started, anti-Morsi organisers closed Tahrir to automobile traffic, only hours after opening parts of the area to passing cars.

Army vehicles intervened to separate the two sides.

Outside Cairo

Meanwhile, clashes broke out in Egypt's Qaliubiya province between supporters and opponents of Morsi.

The clashes led to the death of two 18-year-olds by gunshots, according to the health ministry.  

Al-Ahram quoted a top official in the ministry of health who said three others were injured – one by birdshot, two hit by train while fleeing the gunfire.

A security source also told Al-Ahram that a police officer was injured by a stone as the deposed president's supporters attacked military and police attempting to separate the two sides.

Security, according to Al-Ahram, was able to reopen the Cairo-Alexandria agricultural road, which they said was closed for 6 hours by Morsi's supporters.

In Damietta, pro and anti Morsi protesters locked horns at El-Sa'a Square.

A tense start to the day

Earlier in the day, Egypt's armed forces have blocked all routes to the defence ministry in Cairo's Abbasiya district on Monday, preventing a march by thousands of Morsi supporters from reaching the building.

Morsi supporters continue their call for Morsi's reinstatement, protesting against what they say was a military coup against Egypt's first democratically-elected leader.

Limited scuffles broke out between pro-Morsi protesters and passersbys who oppose the march.

Hundreds of pro-Morsi protesters have gathered at the High Court on Ramses Street, a main road in downtown Cairo. They were joined by another march by several thousands of Morsi supporters moving from the Engineers' Syndicate building on Ramses.

The rally has obstructed traffic movement on Ramses Street and the nearby 26 July Street.

On Sunday, the army also stopped two women's marches, protesting the killing of at least three female protesters in Friday's Mansoura clashes, from reaching their destinations in Cairo. One was headed to the defence ministry while the other to the National Council for Human Rights in Giza.

Egypt's army deposed Morsi on 3 July following mass nationwide protests against him. Head of High Constitutional Court Adly Mansour was sworn in as interim president the next day.

The National Alliance for Legitimacy Support, a coalition of Islamist parties led by the Muslim Brotherhood from which Morsi hails, has been staging protests and sit-ins across Cairo and several governorates calling for Morsi's reinstatement.