MOGADISHU, Somalia, (AP) – Fighting in Somalia’s capital has killed 31 civilians and wounded 60 in the past 24 hours, a local human rights group said Tuesday.

The battles began Monday when insurgents attacked government bases, said Sudan Ali Ahmed, chairman of Elman Human Rights, an independent Somali group.

His organization arrived at the death toll by contacting hospitals and doing its own surveys throughout the city.

“Thirty-one civilians were killed and another 60 were wounded in the past 24 hours,” Ahmed told The Associated Press.

Ethiopian troops, who are in Mogadishu to protect Somalia’s fragile government, opened fire after a bomb went off near their base, he said.

The blast was followed by a bomb attack on a public minibus, several grenade explosions and a gunbattle with police, witnesses and authorities said.

Mogadishu, one of the world’s most violent cities, has been ravaged by fighting that pits Somali troops and their Ethiopian allies against insurgents who are trying to topple the fragile administration. Thousands of civilians have been caught in the crossfire this year, killed by roadside bombs, mortar and grenade attacks and land mines.

Islamic militants vowed to conduct an insurgency in December, when they were toppled by Ethiopian troops supporting Somalia’s government. Somalia has been mired in chaos since 1991, when warlords overthrew dictator Mohamed Siad Barre and then turned on each other.

Somalia’s U.N.-backed government was formed in 2004 but has struggled to assert any real control.

The latest bloodshed comes as a leading human rights group denounced all sides in the conflict, saying they have committed serious violations of humanitarian law, with indiscriminate attacks on civilian neighborhoods and hospitals.

“None of the parties has taken — as international law requires — all feasible precautions to spare the civilian population from the effects of attacks,” New York-based Human Rights Watch said in a report released Monday.