BAGHDAD -- After a heavily guarded walk through a newly fortified Baghdad market, Sen. John McCain declared that the American public was not getting "a full picture" of the progress unfolding in Iraq.

McCain, who is seeking the Republican presidential nomination, cited a drop in murders, the creation of a constellation of joint U.S.-Iraqi military outposts and a rise in intelligence tips as signs of the progress.

"These and other indications are reason for cautious optimism," said McCain, of Arizona, voicing an observation increasingly heard from U.S. officials.

The senator and three other Republican members of Congress appeared most impressed by their visit to Shorja market, citing the hour they spent there as proof that Baghdad was getting safer under a nearly seven-week-old security offensive.

"Never have I been able to drive from the airport, never have I been able to go out into the city as I was today," said McCain. "But I am not saying 'Mission Accomplished.' ... It's a very difficult task ahead of us."

His comments came on a day when the military reported that six American soldiers were killed by roadside bombs southwest of Baghdad. Murder rates are down, but suicide bombings continue to plague the capital, and violence in other parts of Iraq is surging.

At least 152 people were killed in suicide bombings that targeted Shiites last week in Tal Afar, according to the Interior Ministry, which would make the attack the deadliest since the U.S.-led invasion four years ago. The strike triggered reprisal attacks against Sunnis that left at least 45 dead.

The visit comes in the midst of a bitter political tussle over pulling U.S. forces out of Iraq. Both houses of Congress have passed legislation calling for deadlines for troop withdrawals that President Bush has vowed to veto. McCain and other congressional Republicans argue that timelines would undercut progress in Iraq. Last week, McCain said it was safe to walk some of the streets of Baghdad.

But McCain and his delegation held Sunday's news conference inside the heavily fortified Green Zone, which houses the U.S. Embassy and Iraqi government offices. Outside the Green Zone, they rode in armored Humvees protected by dozens of U.S. soldiers and wore bullet-proof vests.

They visited a joint U.S-Iraqi military outpost in Karrada, an upscale central Baghdad neighborhood that Iraqis view as one of the capital's safer neighborhoods.

Part of the Shorja market, normally one of the capital's busiest commercial districts, is now fortified with blast walls and barriers that cut off vehicle traffic. In February, a truck bomb killed 137 people, and injured scores. Last month, another bomb exploded near a Shiite mosque in the market, killing eight and wounding nearly three dozen.

"We were warmly welcomed," said Sen. Lindsey Graham, a South Carolina Republican, who was part of the delegation. "I bought five rugs for five bucks. People were engaging."

"I, too, find myself leaving my day at the market in Baghdad with a new sense of cautious optimism that freedom might just work for these people," said Rep. Mike Pence, R-Ind.

Pence said he was deeply moved by his ability to "mix and mingle unfettered among ordinary Iraqis" and to have tea and haggle over the price of a rug. The Shorja market, he said, was "like a normal outdoor market in Indiana in the summer time."

Gen. David Petraeus, the top U.S. commander, led the tour through the market. Petraeus took off his helmet and put on a soft hat and instructed the politicians to do the same, Pence said. But he acknowledged they left their protective vests on.

Amir Raheem, 32 , a floor carpeting merchant at the Shorja market, disagreed with the upbeat assessment of the congressional visitors.

"Just yesterday, an Iraqi soldier was shot in his shoulder by a sniper, and the day before, two civilians were shot by a sniper as well," he said.

He said Sunni insurgents routinely clashed with Shiite militiamen or with Iraqi soldiers and policemen in the area.

"Everybody closes their shops by 2:30 p.m.," said Raheem.

While the congressional delegation reported seeing crowds of Iraqis shopping in the market, he added that represented a sliver of the customers he used to see.

"It is not even 10 percent of our work before the bombings, because people are afraid to come and it is harder to move," said Raheem.

Worse, he said the closure of the main street by barriers has affected his business. If it was so safe, he said, "let them open the street, for the market has died since they put them there."

Sunday, he said, U.S. soldiers were present in large numbers during the congressional visit and wouldn't let customers "even cross the street to the other side."

At the news conference, McCain criticized Western and Iraqi journalists, including many who had covered Iraq since the U.S.-led invasion in 2003, for not reporting the good news in Iraq.

One Iraqi journalist, speaking in English, asked him: "I just read on the Internet that you said there are areas in Baghdad that you can walk around freelyfi"

"I just came from one," replied McCain.

"Yeah, and which area would that befi" the journalist asked.

"What kind of security [did] you [have] todayfi" asked another journalist.

"Gen. Petraeus goes downtown almost every day," replied McCain. "Of course, he has protection and we had protection today. Things are getting better in Iraq, and I am pleased with the progress that has been made."

After the news conference, reporters asked a U.S. Embassy official for the name of the market the delegation had visited. He declined to identify it, saying the market could come under attack. On Sunday night, U.S. military and embassy officials said it had been Shorja.

This story appeared in The Daily Herald on page A1.