BAGHDAD, (AP) – Iraqi troops have detained 46 suspected militants and killed five others in a new operation in eastern Diyala, the army said Saturday, while a U.S. soldier was reported killed in an explosion in the volatile province.

Iraqi Prime Minister Nouri al-Maliki’s office, meanwhile, confirmed that he had received an invitation for his Turkish counterpart to visit the country to discuss Turkey’s demand that Baghdad crack down on guerrillas of the Kurdistan Workers Party, or PKK, in northern Iraq but no date has been set.

“I think that the date will be set soon,” government spokesman Ali al-Dabbagh said.

In violence Saturday, a bomb left on a minibus also exploded shortly after noon in the predominantly Shiite area of Baladiyat in eastern Baghdad, killing at least five Iraqis and wounding 11, police said. A mortar attack also struck the eastern outskirts of Baghdad, killing two people and wounding four, another officer said. Both spoke on condition of anonymity because of security concerns.

U.S. and Iraqi forces have stepped up efforts in recent weeks against the violence in Diyala, particularly in the provincial capital, Baqouba, 35 miles northeast of Baghdad. Sunni and Shiite extremists fled to the area as U.S. and Iraqi forces began an offensive in the capital.

The Iraqi army said the operation launched Wednesday in several areas and villages in eastern Diyala, which is near the Iranian border, also led to the freeing of a kidnap victim and the discovery of two car bombs and six other explosive devices, as well as the capture of 46 suspects and the killing of five others.

American and Iraqi forces were continuing operations to clear Sunni extremists from Baqouba as well. U.S. troops regained control of the western half of the city last month and launched operations into the rest of Baqouba on Tuesday. The Iraqi army statement said 13 insurgents were killed and 16 detained in the city.

The Americans said earlier this week that they have killed at least 67 al-Qaeda operatives in Baqouba, arrested 253, seized 63 weapons caches and have destroyed 151 roadside bombs since last month.

A roadside bomb killed a U.S. soldier in Diyala province on Friday, the American military said in a separate statement that provided no details about where the attack occurred. The death raised to at least 3,631 members of the U.S. military who have died since the Iraq war started in March 2003, according to an Associated Press count.

Separately, the U.S. military announced the detention of a man accused of being behind the recent increase in powerful roadside bombs Washington believes are smuggled in from Iran as well as mortar and rocket attacks against American forces east of Baghdad.

The militant leader also was suspected of intimidating Iraqis working with U.S. forces, kidnapping and killing rivals and extortion activities through his water distribution company and gas station enterprises, according to the statement. He was captured along with four other suspects in a raid by ground forces in Jisr Diyala, 12 miles southeast of the capital, it said.

The U.S. has launched several offenses in and around Baghdad to try to reduce the level of violence so that Iraq’s sectarian and ethnic groups could negotiate power-sharing agreements to provide for long-term stability. Although the offensives have reduced violence in the capital somewhat, progress on the political front has been slow.

U.S. military officials also have been signaling for weeks that improvements in Iraqi security forces had not lived up to expectations — especially in the national police, which is widely believed to be infiltrated by Shiite militiamen.

On Friday, Maj. Gen. Rick Lynch, who commands U.S. troops south of Baghdad, said it would take until the summer of 2008 to consolidate recent gains in his area, which controls land routes into the capital from the east and south.

Last week, the chairman of the Joint Chiefs of Staff, Gen. Peter Pace, said the number of combat-ready Iraqi battalions able to fight independently has dropped from 10 to six in recent months despite an increase in U.S. training efforts.

Those grim assessments follow years of optimistic public statements from the Pentagon about the progress in Iraqi security forces and have fueled calls in the Democratic-controlled Congress to begin withdrawing from Iraq.

Lt. Gen. Raymond Odierno, the commander of day-to-day operations in Iraq, said Thursday that he would need “at least until November” to know if improvements in Iraq represent long-term trends.

But he issued a statement Friday clarifying that the statement did not change a September timeframe for top U.S. commander Gen. David Petraeus to report on progress to Congress.

For months, Republicans in particular have regarded September as pivotal. If substantial gains could not be found by then, they say President Bush would have to rethink his military strategy, which relies on 158,000 U.S. troops.

“There is no intention to push our reporting requirement beyond September. Nothing I said yesterday should be interpreted to suggest otherwise. My reference to November was simply suggesting that as we go forward beyond September, we will gain more understanding of trends,” Odierno said.

The White House also said Friday it has not changed the timetable for assessing progress in Iraq.