BAGHDAD – U.S. military officials said Saturday that overall American troop levels in Iraq will drop by about 5,000 next month when a combat brigade completes its withdrawal from the country.

The U.S. Army’s 3rd Brigade, 1st Cavalry, which primarily has been operating in the country’s volatile eastern Diyala province, would be the first of five brigades to depart Iraq without being replaced over the next several months, officials confirmed.

The pending departure of the 3rd Brigade was announced earlier this month, but the number of soldiers was reported as 3,000 and the withdrawal was said to be scheduled for January.

“The redeployment without replacement reflects overall improved security within Iraq as well as the improved capability of the Iraqi security forces and the emergence of concerned local citizens,” U.S. Navy Rear Adm. Gregory Smith, director of the Multinational Force-Iraq’s Communications Division said.

Earlier this year, the U.S. military announced plans to reduce troop numbers by about 20,000 by July 2008. The current number of soldiers serving in Iraq stands at around 162,000.

The departure from Diyala of the 3rd Brigade, 1st Cavalry following a 15-month tour in Iraq, would not mark the end of operations in the region, U.S. military officials said.

On Tuesday, troops from the Army’s 4th Stryker Brigade Combat Team, 2nd Infantry Division, located near Baghdad, will begin to deploy to the region and continue to assist Iraqi forces and residents to secure the province, Smith said.

While U.S. officials said that the redeployment would not lessen troop levels in Diyala, it would spread U.S. forces thinner by sending some troops now in Baghdad to the region.

Diyala, a province that borders Iran, had been a Qaida in Iraq stronghold and was wracked by sectarian violence in the past.

Senior U.S. commanders are watching the changes in Diyala closely to see if security gains achieved over the last six months continue to hold.

Any spike in violence could affect how the planned withdrawals of the four additional U.S. brigades are implemented.

(Begin optional trim)

Before the surge of troops in Diyala, which has a population of about 1.6 million people, there were hundreds of significant acts of violence, including suicide attacks and abductions, Sutherland said. Such violence has decreased by more than 68 percent since April, and following an American offensive to flush out al-Qaida.

Ibrahim Bajlan the speaker of Diyala provincial council agreed that security in the region had improved “dramatically.”

But he warned that violence continued on the outskirts of Baqubah.

There are concerns in Baqubah that former insurgents could return if Prime Minister Nouri al-Maliki’s Shiite-led government does not drop its resistance to allowing former Sunni Arab insurgents to become members of the Iraqi police force.

(End optional trim)

Times staff writers Peter Spiegel in Washington, D.C., and Saif Rasheed and Tina Susman in Baghdad and a special correspondent in Diyala province contributed to this report.

AP-NY-11-24-07 1709EST