Cairo, Jul 9 (IANS): At least 42 people were killed Monday in clashes outside a military facility in the Egyptian capital of Cairo, the country's health ministry said, as army said it was a result of an attack by ousted president Mohamed Morsi's supporters.

Morsi's Muslim Brotherhood (MB) party, in a statement, blamed army for the killings, while claiming that the dead were the ousted president's supporters.

The party said the security forces fired at the protesters at dawn outside the headquarters of the Republican Guard in Cairo's Nasr City area, where Morsi is reportedly detained, Xinhua reported.

"Morsi's supporters were praying while the police and army fired live rounds and tear gas at them," the statement said.

The Freedom and Justice Party (FJP), the political wing of the MB, said the incident was a "human massacre" against peaceful citizens who protested against "a military coup" which ousted the elected president last week.

Last week, the army ousted Morsi after millions of people took to the streets to protest against the Islamist-oriented president's "poor performance" since he came to power a year ago.

The FJP then urged for "an uprising by the great people of Egypt against those trying to steal their revolution with tanks".

However, state-run Nile TV quoted a source close to the army as saying that there was video footage recorded by soldiers showing that it was the supporters of Morsi who attacked them first, and they were forced to fire back under the threat of murder.

"We managed to flee, after being attacked by Morsi's supporters with weapons," one of the soldiers said.