CAIRO – Egypt’s military officials moved swiftly Saturday to prosecute protesters they blamed for an attack on the Defense Ministry, in an attempt to put down increasingly violent protests against their authority just weeks before the country’s presidential election.

The fierce street battles on Friday raised to new heights the tension between the generals who assumed power after Hosni Mubarak stepped down last year, and their critics, predominantly secular and liberal groups but now spearheaded by hard-line Islamists.

At least a hundred protesters have been killed in violent confrontations with security agencies since Mubarak’s ouster. But the military’s response to Friday’s demonstration near its headquarters was significant in how swiftly they moved to detain protesters.

Military prosecutors interrogated hundreds of demonstrators, referring some 300 of them to 15 days detention pending investigation into accusations of attacking troops and disrupting public order, a prosecution official said Saturday.

At least two detainees are accused of killing a soldier in Friday’s violence, the official said.

Political tension has been building during an election run-up marred by legal pitfalls, unclear presidential powers and activists’ fear that the military is seeking to back a candidate who will cater to its interests.