Cairo (CNN) -- Egyptian security forces opened fire on supporters of the deposed president, Mohamed Morsy, and the Muslim Brotherhood, early Monday, killing more than 40 people.
Witnesses said the military and police fired when protesters had taken a break from holding a vigil at the Republican Guards headquarters to say their morning prayers. Morsy is reportedly detained there after his arrest Wednesday.
The health ministry put the number of fatalities at 42, and said 322 others were wounded.
The military offered a different version. It said it was forced to fire when an "armed terrorist group" tried to raid the headquarters. An interior ministry statement said two security force members died in the clashes.
The Monday morning violence further deepened a crisis in the country -- the Arab world's most populous -- where Morsy supporters have been squaring off daily with the military.
CNN counted at least eight bullet-riddled bodies and up to 40 wounded at the chaotic emergency facility in the Egyptian capital, down the street from the site of the shooting. The upper bodies of the victims appeared to be peppered with shotgun pellets and bullet wounds.
Doctors tended to the victims, performing surgeries in many cases before shipping them out to other facilities. Egyptian flags were draped over those who did not survive.
In the midst of the escalating tensions, state radio reported that two soldiers had been kidnapped by Morsy supporters in eastern Cairo.
Party withdraws from talks
Reacting to the shooting at the Guards headquarters, the Al-Nour party -- which supported Morsy's ouster -- withdrew from all talks about forming an interim government.
"We will not remain silent on the Republican Guards Massacre," party spokesman Nader Bakkar said.

Stepping up security

The developments came as protesters took to the streets again, where, for weeks, arguments have turned to clashes.
Ahead of Monday's events, more than 30 people had died and 1,400 had suffered injuries since Wednesday's coup.
Egypt's military said in a statement over the weekend that it was stepping up security efforts for the demonstrations.
"We also warn against any provocation or clashes with the peaceful demonstrators," the statement said. "Anyone who violates these instructions will be dealt with firmly in accordance with the law."

Supporters vow peaceful protests

Meanwhile, the Muslim Brotherhood's political party vowed that protests would be peaceful and accused authorities of planning to send fake bearded men into Cairo's Tahrir Square to incite violence.
"This is so they can claim that the supporters of the elected-president and the Islamic groups are attacking the peaceful demonstrators. ... We warn those who play with fire that any sectarian incitement at this critical time will not be in the interests of anyone in our beloved Egypt," the Freedom and Justice Party said in a statement posted on its Facebook page.
Human Rights Watch called for the country's military and political leaders to do more to stop the bloodshed.
"All sides need to tell their followers to refrain from actions likely to lead to violence and loss of life," Joe Stork, deputy Middle East and North Africa director at Human Rights Watch, said in a statement. "At the same time, the security forces need to show that they can act professionally and effectively to stop the violence without resorting to unlawful lethal force."

Policewoman: Allah Akbar.

Kenny4lyfe: If these should continue, I fear Egypt shouldn't become the next SYRIA oOh!
God help Africa!