Marine Corps News: Reporter John Koopman and the 3/4 Marines during the Iraq War www.MarineParents.com

CENTRAL IRAQ -- Horrible weather and persistent attacks by Iraqi militia forces slowed the 1st Marine Division advance on Baghdad Wednesday.

The Marines were on their way to engage Iraqi regular military units, even as the Army's 3rd Infantry Division started to deal with the Republican Guard near Baghdad, when they ran into one of the worst sandstorms to hit the region in recent memory.

The column of tanks, armored personnel carriers, trucks and supply vehicles came to a grinding halt Tuesday afternoon as winds gusted to 50 and 60 miles per hour, carrying dust, sand and rocks along with it.

Men buttoned up their vehicles and tried to ride out the storm. But the grit and dirt found its way into every crease in the vehicles, making breathing difficult and sleep nearly impossible.

Marines were reduced to a bleary-eyed torpor as they sweated in cramped Humvees and armored assault vehicles from late in the afternoon until the middle of night.

The sand storm was replaced by heavy rains that made the dirt into an almost cement-like paste. But it was enough to get the column moving again and, after refueling, the vehicles moved out in pitch-black darkness.

"We got pretty lucky that we didn't have anyone get hurt," said Lt. Col. B.P. McCoy, a battalion commander with the 1st Marines. "Sometimes brute force and ignorance can get you through."

By morning, the Marines had advanced further north but were bogged down when the advance unit came into contact with Iraqi militia forces. Artillery and small arms fire could be heard in the distance as troops up and down the column stopped, spread out and started patrolling the area.

It was unclear whether the slowdown and patrolling signaled a new strategy for military operations in the region, or if it was simply a momentary response to a specific enemy action.

"This is a problem we have to deal with," McCoy said. "We don't want to let them get in any cheap shots."

Another wind, not nearly as fierce as the previous day's, kicked up and visibility was reduced. A Huey helicopter crashed in this environment, but it was unclear whether the cause was weather, mechanical or from ground fire.

The Marines took the slowdown in stride for the most part.

"We're good to go, sir," said Pfc. Gary Miranda, 19, of Ukiah. "We're doing our jobs."

Others were more impatient, and said they just wanted to get into battle, rather than sit around and wait for something to happen.

"This is going a lot slower than I thought it would," said Cpl. Mike Franke, 21, of Big Bear (San Bernardino County). "Everything seems like it's getting bogged down. We're ready to go now."

A lot of the fighting has been done by attack helicopters and tanks. The infantry and small weapons units have not seen a lot of action. A lot of those Marines stay inside the armored assault vehicles and rarely get out to fight.

Many were in harm's way in the fighting around Basra, however, but mostly they took small arms and mortar fire, and then called in air, mortar or artillery strikes on suspected Iraqi positions.

Lance Cpl. Ving Ly, 21, of Stockton, said he and his 81mm mortar unit were ambushed near Basra. He and his unit got out of their HumVee, he said, and started setting up their mortar when bullets hit the dirt all around them.

"I looked around and yelled "staff sergeant, they're shooting at me,'" Ly said, recounting the incident.

The fighting was so intense, the mortar unit had to resort to desperate measures to get their guns working. Mortars need guide post staked out to show their fields of fire, but they were on pavement and there was no way to pound the stakes into the ground.

So they sent a junior Marine out to lie on the pavement, M-16 in one hand and guide stake in the other.

"You're not supposed to do it that way, but it worked," said Cpl. John Hanock of Texas.

The fiercest fighting was done by tanks and they are expected to play a major role in the fight for Baghdad.

Sgt. Jason Perez, 31, of Chino, said he was in a tank near an oil field in Basra when an Iraqi T-55 tank fired a round at his commander's vehicle. He returned fire and blasted the other tank.

The M1 Abrams tanks then went on to destroy several Iraqi armored personnel carriers. Some were empty and some not.

Perez said the T-55 is an old model Soviet-era tank and not nearly a match for the M1. The same goes for the later model T-72, which the Marines expect to encounter in Baghdad.

"It's really not much good," he said. "It's certainly no match for us. This tank can get hit by a 500-pound bomb and the crew won't necessarily get hurt."

The Iraqi tank crews who face the M1, he said, are either very gutsy or are true believers in their cause.

"I'm a student of history, and this seems to me a bit like when the American Army was rolling across Europe at the end of World War II," he said. "It feels historic.

Perez said he felt like he was a liberator, like he was doing a good thing for the Iraqi people.

"We were rolling through some of those areas and saw kids looking pretty hungry," he said. "I tossed them some MREs (field rations). I know I'm not supposed to, but it felt like the right thing to do."

E-mail John Koopman at jkoopman@sfchronicle.com.