Marines from Regimental Combat Team 6 have completed their “relief-in-place” with Regimental Combat Team 5, taking responsibility for operations in eastern Anbar province, an area that includes the city of Fallujah.

Though officers and command staff from RCT-6 have been in the country for several weeks, the change of command took place Wednesday morning, U.S. military officials said Thursday.

“We look forward to continuing with the successes that our predecessors have achieved,” Col. Richard L. Simcock, commander of RCT-6, said. “Regimental Combat Team 5 has done a phenomenal job in the area of operations. The Marines and sailors of the 5th Marine Regiment deserve a great deal of credit in being the supporting element for the Iraqi army and Iraqi police.”

The Camp Lejeune, N.C.-based RCT-6 will focus on “assessing, training and operating with Iraqi security forces in the greater Fallujah area,” officials said.

The regiment contains units from all four Marine Divisions and includes units that were assigned under RCT-5 and have not yet hit their scheduled return rotation date.

The units include three infantry battalions from Camp Lejeune; an infantry battalion from the 24th Marine Regiment in Michigan; a reconnaissance battalion from Okinawa, Japan; and a tank company, engineer company, amphibious assault company and artillery battery from Camp Lejeune.

RCT-6 is scheduled to be in Iraq for a year, officials said, though the subordinate units will continue on their planned rotations. The command staff of RCT-5 also had served a year in Iraq, and now returns to Camp Pendleton, Calif.

“I feel very good about what we have been able to contribute to Iraqi security forces’ development,” Col. Larry D. Nicholson, RCT-5 commander, said. “The future of the city resides not in the Marines, but in the Iraqi army and Iraqi police.”