American forces suffered a deadly 24 hours in Afghanistan, with eight troops killed in attacks including an audacious Taliban raid on a police compound in the key southern city of Kandahar, officials said Wednesday.

An Afghan policeman stands guard at a police base which came under attack last night in Kandahar, south of Kabul, Afghanistan, Wednesday, July 14, 2010. [Agencies]

The US and its coalition allies have warned that violence and troop casualties are likely to mount this summer as thousands of new forces fan out across southern insurgent strongholds in a bid to turn around the nearly 9-year-long war.

However, a top US commander in the south said Wednesday that the new operation should start reducing violence in coming months.

So far in July, 45 coalition troops have died in Afghanistan, 33 of them Americans, continuing the upward trend of the previous month, which was war's deadliest for the NATO-led force, with 103 international soldiers killed.

A suicide attacker slammed a car bomb into the gate of the headquarters of the elite Afghan National Civil Order Police late Tuesday night in Kandahar, the international force said. Minutes later, insurgents opened fire with machine guns and rocket-propelled grenades.

Three US troops, an Afghan policeman and five civilians -- three interpreters and two security guards -- died in the attack, but NATO said the insurgents failed to enter the compound.

Four more American troops were killed elsewhere in the south Wednesday by a roadside bomb, while one more US service member died the same day of wounds from a gunbattle, also in the south. NATO gave no further details of those attacks.

The special Civil Order Police had only recently sent 600 more officers to Kandahar to set up checkpoints along with international forces to try to secure the south's largest city, the spiritual birthplace of the Taliban.

Taliban spokesman Qari Yousef Ahmadi telephoned reporters Wednesday to claim responsibility for the attack. The insurgents, who are prone to exaggerate death tolls of their enemies, claimed 13 international troops died in the raid.

Also in Kandahar, a pro-government cleric and member of a local people's council was gunned down in a mosque Wednesday. Haji Khalifa, a member of the Pajawai district shura, or council, was shot dead as he prayed, said provincial shura member Agha Haji Lalai.