The Netherlands' Defense Ministry says two Dutch soldiers and two allied Afghan soldiers were killed in friendly fire incidents Saturday night in southern Afghanistan.

The top Dutch military commander, General Dick Berlijn Sunday said darkness and poor weather conditions played a role in the mistakes.

He said Dutch soldiers killed two of their own men during a nighttime battle in Uruzgan province. Also, he said, Dutch soldiers shot dead two Afghan troops who approached a wounded Dutch soldier. The Afghans were not in uniform.

In other news, Britain's Defense Secretary Des Browne says his nation's troops could be in Afghanistan for decades, saying there is a risk the country could again become a haven for terrorists.

In an interview published Sunday by The People newspaper, Browne says Britain's military commitment will reduce over time. He said Afghanistan will only be secure when the international community works with the Afghan government and military.

Afghans stand around coffin of a suicide attack victim in Lashkar Gah, provincial capital of Helmand province, 13 Jan 2008

In volatile southern Afghanistan Sunday, Afghan authorities say at least nine police officers were killed in two separate militant attacks.

Authorities say Taliban militants stormed a police post in the Maywand district of Kandahar province, killing at least eight officers.

In neighboring Helmand province, officials say a suicide bomber blew himself up Sunday, killing one police officer and wounding at least four other people.

Police say the bomber, with explosives strapped to his body, tried to enter the house of a senior police official in the town of Lashkar Gah, and was stopped by guards.

Officials say he detonated his explosives, killing a policeman and wounding two children along with at least two other police officers.

Some information for this report was provided by AP.