Egyptian police and supporters of ousted president Mohamed Morsi holed up in a Cairo mosque exchanged heavy gunfire on Saturday afternoon, an AFP correspondent said.
After security forces had besieged the mosque since Friday night, police managed at one point to get inside and drag some of the holdouts outside, where they were confronted by hostile crowds.
Police fired into the air to keep the mob at bay.
The correspondent said police and troops began to storm the Fath mosque in the centre of the capital when they were fired on from the minaret.
The security forces responded by firing tear gas into the mosque and pressing their assault.
In the process, they managed to drag outside seven or eight men and were then confronted with angry neighbourhood residents who attacked them with sticks and iron bars.
One man dressed in civilian clothes was wounded by police gunfire.