DUND, Afghanistan - A suicide bomber wearing a police uniform blew himself up inside a police headquarters in southern Afghanistan on Monday, killing eight people, an official said.

Three police and five civilians died in the attack in Dund district, about 15 kilometres south of Kandahar city, said Zalmay Ayubi, the spokesman for Kandahar's governor. Six people were wounded, he said.

Canadian soldiers and Afghan police stood guard at the blast site and ordered journalists not to take photos, according to an Associated Press reporter at the scene. A spokesman for NATO's International Security Assistance Force said he would investigate the report.

The Canadian soldiers refused to let Afghan police approach the blast site, the reporter said.

Kandahar, where many of Canada's more than 2,500 troops are currently stationed, is the spiritual birthplace of the Taliban and continues to be a militant stronghold. Afghan police frequently suffer from Taliban attacks from roadside and suicide bombs.

A roadside bomb also killed three police in the eastern province of Paktia on Monday, the Interior Ministry said.

Taliban attacks have spiked the last three years, as militants have taken control of wide swaths of countryside. U.S. President Barack Obama is sending 21,000 additional American troops to bolster the record 38,000 already in the country.

Officials from more than 70 countries are attending a conference in the Netherlands on Tuesday focusing on Afghanistan. The United States, which announced a new strategy for Afghanistan and Pakistan last week that will focus on fighting al Qaeda, is expected to explain its policies for the region.