By Rodney Joyce
KABUL, May 3 (Reuters) - NATO forces in Afghanistan vowed on Thursday to improve coordination with Afghan authorities to avoid civilian casualties, after a warning from President Hamid Karzai that his people were losing patience over continuing bloodshed.
The push to ease the toll on civilians came as a roadside bomb blasted an Afghan army bus in Kabul, killing the driver and wounding 29, hours after gunmen shot dead an ex-premier.
Nearly 60 civilians have been killed in raids by U.S.-led coalition troops in the past week, Afghan officials say, sparking four days of anti-American, anti-Karzai protests.
"There's absolutely room for additional coordination," Lieutenant Colonel Maria Carl, a spokeswoman for NATO's ISAF security force, told reporters asking about civilian deaths and Afghan concerns they were not involved in planning Western military operations.
"We are seeking new ways, all of us in country -- the government, the coalition, ISAF -- to improve these processes."
Protesters called this week for the removal of Karzai for failing to stop the civilian killings, which have come amid an upsurge in violence as the Western-backed government and the Taliban push for a decisive advantage in their battle for the country.
Karzai again called for increased military co-ordination on Wednesday at a meeting with the U.S. ambassador and United Nations, NATO and EU representatives, and warned of serious consequences for all if civilian deaths were not curbed.
Most of the recent civilian deaths were reported in the western province of Herat, an area not known as a Taliban stronghold, prompting many Afghans to reject initial reports from U.S.-led coalition forces that the dead were 136 Taliban.
NATO officials said inquiries were under way into what happened in Herat, where Afghan officials say 51 civilians were killed.
Another protest erupted in Herat on Thursday after an Afghan soldier shot dead a man on a motorcycle, officials said.
While the protests have been mainly small, government officials, NATO and analysts all warn that a steady stream of civilian deaths will inevitably erode support for Karzai and the war against the Taliban, who were driven from power in 2001.
A failure to curb rampant corruption and rebuild the country after decades of war has also weighed on the government.
Thousands of civilians have been killed since U.S.-led troops ousted the Taliban government for sheltering al Qaeda leaders.
In Kabul, Taliban militants claimed responsibility for a remote-controlled bomb blast that ripped into the side of an Afghan army bus on Thursday, killing the driver and wounding 29 soldiers and civilians.
The bomb, hidden in a cart, was triggered in a crowded area of the city as the bus took army officers and soldiers to work.
Kabul has been relatively safe compared to the troubled south and east but there have been around 10 attacks on Afghan and foreign forces in the city this year.
Late on Wednesday, Senator Ustad Farid, a member of the upper house of parliament and briefly prime minister during the civil war of the 1990s, was gunned down in his car outside his house.
Police said they suspected the killing, the second of a lawmaker this year in the capital, was due to a feud rather than a Taliban attack. (Additional reporting by Sayed Salahuddin and Reuters Television)