KANDAHAR, Afghanistan (AP) – A suicide bomber in a car struck a NATO-Afghan military convoy Tuesday, killing one civilian and wounding two others, a day after a bomb at a market left 21 civilians dead and 43 wounded, officials said.

Another bomb, detonated by remote control, killed two police on patrol in Helmand province, an official said.

The suicide bomber hit the military convoy on the main road linking Kandahar with the city’s airport, said. Col. Sher Shah, who was in the convoy. No NATO soldiers were wounded. A civilian driving near the convoy died in the blast, while another civilian and an Afghan soldier were wounded, Shah said.

The Taliban have increased suicide attacks this year, borrowing tactics from militants in Iraq. The escalation in the Taliban insurgency has stoked bitter fighting. More than 1,600 people, mostly militants, have died across Afghanistan in the past four months, according to an Associated Press tally of reports by U.S., NATO and Afghan officials.

The remote-controlled bomb hit a police vehicle on patrol in Grieshk district of Helmand province killing two officers, said Ghulam Muhiddin, the Helmand governor’s spokesman. He blamed the Taliban.

Another remote-controlled bomb went off in east Kabul shortly after a NATO vehicle patrol drove past, but no one was hurt, said Interior Ministry spokesman Yousef Stanezai.

On Monday, a suicide bomber targeting a former police chief killed 21 people and wounded 43 in a market in the Helmand provincial capital of Lashkar Gah. The bomb initially killed 17 people, but four of the wounded later died, officials said.

NATO and the United Nations also characterized the bombing as a suicide attack.

But Qari Yousaf Ahmadi, who claims to speak for the Taliban, said Monday’s attack was conducted with a remote-controlled bomb, and that it targeted a former Lashkar Gah police chief because he had served under the pro-Communist government during the Soviet occupation of the 1980s. The target and his son were killed.

“We are very sad about the civilian casualties,” Ahmadi, whose ties to the Taliban leadership are unclear, told an Associated Press reporter in a phone call from an undisclosed location. “We only wanted to kill this former police chief.”

It was not immediately clear why Ahmadi’s account of the attack conflicted with the other reports that it was a suicide bombing.

The attack was the second major bombing to kill civilians this month in southern Afghanistan, which is undergoing its bloodiest period of fighting since the U.S.-led ousted the hard-line Taliban regime in late 2001 for hosting Osama bin Laden.

Meanwhile, two New Zealand soldiers serving in Afghanistan’s Bamiyan province were flown to a military hospital after being injured in a road accident, a New Zealand defense spokesman said Tuesday. The soldiers were injured when the part of the road they were on gave way, causing their vehicle to roll down a 60-foot slope.