US troops killed 26 alleged insurgents in what was reported to be a Sunni stronghold west of Baghdad today.
They also arrested 60 suspected militants overnight in a security clampdown to stem violence in the capital.
The sweep through the southern Baghdad district of Arab Jabour targeted a suspected bomb-making cell linked to attacks across the city of seven million.
"The group has been reported to be planning and conducting training for future attacks, like the attack in Mahmudiya July 17th that killed 42," the US military claimed in a statement.
Beefed-up US and Iraqi forces this week began a systematic operation to claim back Baghdad's most dangerous rebel strongholds in an attempt to restore security and shore up confidence in the new Shia-led government.
Iraqi soldiers killed eight militants and arrested seven in a separate operation in the Um al-Maalif district of southern Baghdad, the Department of Defence said in a statement.
US officers now talk openly about the risk of a full-scale civil war unless they can calm conditions in Baghdad.
Some 50,000 US and Iraqi forces are taking part in Operation Together Forward. Similar campaigns have failed in the past but Washington hopes to cut violence significantly by the end of September.