Heavy gunfire could be heard as clashes between troops and anti-military protesters spread around the defence ministry in Cairo on Friday, May 4 leaving 59 injured according to the health ministry, AFP reported.

The health ministry said most of the injured had been treated on the spot in the Abbassiya neighborhood, where military police had used tear gas and water cannon under a volley of rocks hurled from both sides.

"During the clashes in Abbassiya, 59 people were injured... of those five are being treated in hospital," said health ministry official Ahmed Al-Ansary in a statement.

Protesters and military police faced off in Abbassiya separated by barbed wire, before troops charged the protesters and began chasing them down the roads leading off the main square.

Heavy gunfire could be heard, an AFP reporter said.

A security official told AFP that the army had fired warning shots in the air in a bid to disperse the protesters.

A military source said that the army had chased down the protesters "with the help of Abbassiya residents and police forces", arresting 40 people he described as "thugs."

Thousands of anti-military protesters took to the streets in both Cairo and Alexandria, days after deadly clashes near the defense ministry raised tensions ahead of landmark presidential elections later this month.