A Marine military policeman with his working dog named "Rocky" watch over the streets of Karabilah, Iraq

The U.S. military says American and Iraqi forces fighting insurgents in western Iraq have encountered strong resistance as they battle to secure the border region and prevent terrorist infiltrations from Syria.

The military says coalition forces have encountered some of the heaviest fighting in the city of Ubaydi since Operation Steel Curtain began 10 days ago. Three Marines and 80 insurgents have been killed since coalition forces entered the city on Monday.

They have found houses rigged with explosives, more than 100 explosive devices and mines, as well as 36 weapons caches.

The operation is intended to restore security along the Euphrates River Valley ahead of next month's parliamentary elections.

Meanwhile, attacks in Baghdad and Kirkuk killed eight policemen Tuesday. And coalition forces say they captured a high level Baath Party leader Hamid Sharki Shadid in Diyala province.