The mother of a Marine sergeant from Roswell, New Mexico who was killed during fierce fighting this week in Iraq says she doesn't believe going to war was for a good cause.

"And yes, our heroes have died in vain — and one of them is my son," Velina Sanchez told an Albuquerque television station while clutching a photo of Sgt. Moses Daniel Rocha (search) in his dress uniform.

Rocha, 33, was fatally shot during fighting that erupted in Najaf, where U.S. helicopter gunships and fighter jets continue to pound Shiite Muslim insurgents.

The fighting, which began early Thursday, threatened to re-ignite the bloody, two-month Shiite insurrection that broke out in April.

The military said two Marines and an American soldier were killed in the Iraqi holy city Thursday, and 12 troops were wounded. But the U.S. Department of Defense had no specific details about Rocha's death.

Gov. Bill Richardson (search) said he was saddened by the death of Rocha, who leaves behind a young son.

"This is the second death in less than a week for the city of Roswell and again points out the tremendous sacrifice of New Mexicans in defending our nation in the war against terror," he said.

Sgt. Tommy L. Gray, also of Roswell, died in Taji after he was caught between two vehicles in his unit's motor pool. The tank mechanic was assigned to the Army 1st Cavalry Division's 215th Forward Support Battalion based in Fort Hood, Texas.

Richardson issued an executive order for all flags in New Mexico to be flown at half-staff in honor of Gray.

He then issued another order for flags to be flown at half-staff for Rocha.

Richardson said he talked to the Marine's mother to offer his condolences and express gratitude for Rocha's willingness to serve his country.

"His sacrifice and his courage will never be forgotten," Richardson said.Rocha is the fifth New Mexico soldier to die in Iraq.

In addition to Gray, Marine Lance Cpl. Aaron Austin, 21, of Lovington, was killed April 26 in Fallujah during his second tour in Iraq. Lance Cpl. Christopher Ramos, 26, of Albuquerque was killed April 5, also on his second tour of duty. Army Specialist James "Heath" Pirtle, 27, of La Mesa, a graduate of Carlsbad High School, died in October.