At least 23 people were killed and scores were wounded Wednesday in the Ethiopian capital, doctors and hospital workers said, as riot police and protesters clashed for a second day over disputed parliamentary elections.

Information Minister Berhan Hailu said the casualty figures had been exaggerated and put the death toll at 11 civilians and one police officer. He said 54 officers and 28 civilians had been injured.

Machine-gun fire and explosions rocked the capital, and armored personnel carriers carrying troops charged down streets littered with burning tires and glass.

Police surrounded Zewditu Hospital, dragging out young men and arresting them. Witnesses said security officials were rounding up young people in various parts of the city.

Abdul Fatal said his 13-year-old daughter, Arabia, suffered shrapnel wounds to her stomach and legs.

"The police were looking for rioters and burst into our compound. They fired tear gas and then threw a grenade," said Fatal, a laborer. "The police then started shooting in the compound. My daughter has never been in trouble with anyone."

Doctors at five hospitals said that the bodies of 23 people killed in the clashes were brought to emergency rooms and that at least 150 people were treated for injuries.

The clashes marked a political setback for Prime Minister Meles Zenawi, promoted by the Bush administration as a progressive African leader and a key partner in the war against terrorism.

The May 15 elections, which gave Meles's ruling party, the Ethiopian People's Revolutionary Democratic Front, control of 60 percent of the Parliament, had been seen as a key test of Meles's commitment to reform. Opposition parties say the vote was marred by fraud.

The clashes came hours after security officials arrested opposition leaders. All 15 members of the Coalition for Unity and Democracy's central committee and about 1,000 supporters were taken into custody, a lawyer who works for the opposition party said.

A woman outside the Black Lion Hospital in Addis Ababa, Ethiopia, reacts to the day's violence.