Weapons caches are turning up with increasing frequency in public places in Iraq — from a bakery to a fish farm — as recent security gains embolden more civilians to come forward with tips, U.S. and Iraqi military officials say.

The odd locations of many of the discoveries reflect the fine line separating civilians from the Shiite and Sunni extremists who don't wear uniforms and often live among them. Many would-be tipsters had previously looked the other way because of intimidation or because they sought protection from local militias.

"These are people who in the past weren't willing to come forth because of the threats from militias," said Maj. Gen. Jeff Hammond, the top commander of U.S. forces in Baghdad. "Now they're telling the Iraqi army they've had it with the militia. 'Don't leave. We want you to stay here.'"

The chief Iraqi military commander in Baghdad, Gen. Abboud Qanbar, said the quality of the tips also has improved.

"Now we are given accurate information and this has enabled us to discover large caches," he told reporters Wednesday. "Now the citizens are cooperating with us. Thus our work is getting better."

Cash rewards are another motivation for tipsters. For the military, it's money well spent: So far this year, U.S. and Iraqi forces have cleared and found 4,950 caches, compared with 6,963 in all of 2007, according to U.S. military figures.

Skeptics, however, warn the weapons found to date are likely a small portion of the overall arsenal. They point out that insurgents on both sides of the sectarian divide have proven adept at getting new arms.

"It seems to me that the amount that has been confiscated is small relative to the amount that might be out there," says John Pike, a military and security analyst who runs the respected Web site GlobalSecurity.org.

"It is an essential part of a counterinsurgency strategy," he said in a telephone interview. "But I just don't see that it has the potential to materially contribute to victory ... because it's just so easy to resupply."

But U.S. military officials point to growing public confidence in recent military successes in Shiite militia strongholds. A U.S.-funded Sunni revolt against al-Qaida in Iraq, in which former fighters joined forces with the Americans, also has provided troops with more information about hiding places.

The trend is particularly evident in Sadr City, a sprawling district in northeastern Baghdad that houses 2.5 million people and has long been dominated by the Mahdi Army militia of anti-U.S. cleric Muqtada al-Sadr.

Fierce fighting broke out in the area after the U.S.-backed government launched a crackdown in late March, but the clashes ebbed after al-Sadr called for a cease-fire.

Usually acting on tips, Iraqi soldiers have rounded up rockets, grenades and other explosive devices from mosques, hospitals and schoolhouses in the aftermath.

Many of those weapons were laid out for reporters at the former Iraqi air base in southeastern Baghdad on Wednesday as the U.S. and Iraqi military showed off their recent gains but warned there was more work to be done.

Iraqi soldiers, with U.S. troops staying on the outskirts of the district, have discovered 51 caches containing 7,820 weapons and other munitions in Sadr City between the start of the operation and June 16, according to figures provided by the U.S. military.

"I don't think it's the bulk of it, but I think it put a big dent in their destructive power," U.S. Maj. Mark Cheadle said, gesturing to the rows of rusty grenade launchers and shiny copper plates used to make powerful roadside bombs known as explosively formed penetrators, or EFPs, which allegedly come from Iran.

Also lined up were an ambulance, buses and several other vehicles that the Iraqi military said had been used to transport weapons and stage kidnappings and other violence before they were confiscated.

But it is the bizarre locations of some of the discoveries that are attracting the most attention.

One recent tip led U.S. soldiers to a bakery in a Shiite militia stronghold in eastern Baghdad. The troops had to fight their way into the storefront, where they found what the military called an "EFP-making factory."

In a feed warehouse in another Shiite area of Baghdad, Iraqi soldiers found 90 122 mm rockets, EFP components, mortar shells and an American unmanned drone that apparently had been downed by mechanical failure.

And in a mainly Sunni area about 20 miles southwest of the capital, U.S. and Iraqi soldiers pulled six 120 mm mortar rounds from the murky waters of a fish farm.