KANDAHAR, Afghanistan - Roadside bombs and battles with Taliban forces killed six police and left 13 Taliban fighters dead or wounded in separate incidents in southern Afghanistan, officials said Friday.

A roadside bomb exploded in Kandahar's Panjwaii district on Friday, killing three police officers and wounding four in a police vehicle, said district police chief Bismullah Khan.

In the nearby Spin Boldak district, a roadside bomb killed two policemen and wounded three others in a border police vehicle, Gen. Raziq Khan said.

Khan said in nearby Arghistan district, a police operation against Taliban fighters on Thursday killed or wounded nine of the militants. He said Taliban fighters took their casualties away but that intelligence sources learned the casualty figures.

In Zabul province, a two-hour gun battle killed one policeman and four Taliban, said acting provincial police chief Hakim Khan.

Violence has spiked sharply in recent weeks in Afghanistan. Some 2,200 people have died in insurgency-related violence this year, according to an AP count based on numbers from U.S., NATO, UN, and Afghan officials.