"Deaths are occurring in Iraq now at a rate more than three times that from before the invasion of March 2003," Dr. Gilbert Burnham, lead author of the study, said in a statement.

The study by Burnham, of the Johns Hopkins Bloomberg School of Public Health, and others is to be published Thursday on the Web site of The Lancet, a medical journal.

An accurate count of Iraqi deaths has been difficult to obtain, but one respected group puts its rough estimate at closer to 50,000. And at least one expert was skeptical of the new findings.

"They're almost certainly way too high," said Anthony Cordesman of the Center for Strategic & International Studies in Washington. He criticized the way the estimate was derived and noted that the results were released shortly before the Nov. 7 election.

"This is not analysis, this is politics," Cordesman said.

The work updates an earlier Johns Hopkins study - that one was released just before the November 2005 presidential election. At the time, the lead researcher, Les Roberts of Hopkins, said the timing was deliberate. Many of the same researchers were involved in the latest estimate.

Speaking of the new study, Burnham said the estimate was much higher than others because it was derived from a house-to-house survey rather than approaches that depend on body counts or media reports.

A private group called Iraqi Body Count, for example, says it has recorded about 44,000 to 49,000 civilian Iraqi deaths. But it notes that those totals are based on media reports, which it says probably overlook "many if not most civilian casualties."

For Burnham's study, researchers gathered data from a sample of 1,849 Iraqi households with a total of 12,801 residents from late May to early July. That sample was used to extrapolate the total figure. The estimate deals with deaths up to July.

The survey participants attributed about 31 percent of violent deaths to coalition forces.

Accurate death tolls have been difficult to obtain ever since the Iraq conflict began in March 2003. When top Iraqi political officials cite death numbers, they often refuse to say where the numbers came from.

The Health Ministry, which tallies civilian deaths, relies on reports from government hospitals and morgues. The Interior Ministry compiles its figures from police stations, while the Defense Ministry reports deaths only among army soldiers and insurgents killed in combat.

The United Nations keeps its own count, based largely on reports from the Baghdad morgue and the Health Ministry.

The major funder of the new study was the Massachusetts Institute of Technology.

It was still unclear whether the depot at Forward Operating Base Falcon was hit by an attack. The cause of the fire was not immediately known, Lt. Col. Christopher C. Garver, a U.S. military spokesman, said.

Explosions from detonating tank and artillery ordnance and small-arms ammunition stored at the site went off for hours after the fire erupted.

Large flames and smoke rose from the region, and flashes from the blasts and showers of sparks were visible on the horizon from several miles away in central Baghdad. The blasts came at times sporadically, at times in rapid succession, lasting into the night.

A spokesman at the base said the blaze broke out in an ammunition holding area, where material was kept temporarily.

Iraqi Interior Ministry Jawad al-Bolani said the blasts had shaken three neighborhoods close to the base but the situation was "under control."

Most of the bodies were blindfolded and showed signs of torture with bullet holes in different parts.

CNN reported another 50 were found later in the day Tuesday.

The almost daily gruesome body findings, assassinations and explosions in Baghdad and other Iraqi cities are seen as a major setback for the Iraqi government's efforts to stem violence and achieve national reconciliation.

The UN and Iraqi officials estimate that more than 100 Iraqis are killed everyday in insurgent attacks and fighting between Sunniand Shiite factions.

Also Monday, a U.S. soldier was killed when his patrol was attacked by insurgents in an eastern part of Baghdad, the military said.

The second soldier, attached to the 25th Combat Aviation Brigade, died of wounds from an explosion during a vehicle patrol Sunday north of the city of Tikrit.

No further details were available, and the soldiers' names were being withheld pending notification of family.

The local leader, speaking from his home in Baquba, said the situation in the area was becoming dire in the face of the recent violence.

"The worst is the direct participation of the national security forces in criminal acts, and the U.S. Army's sudden disappearance from the scene as soon as those murderers show up," he said. Many have been killed, and hundreds arrested in the province, he said.

The al-Tawafuq Sunni party has demanded a full investigation into the violence in Baquba, and immediate release of the detained civilians. "We are sure the arrests were made under sectarian flags and those detainees are innocent farmers captured in their own plantations," the group said in a statement.

An Iraqi army colonel told reporters in Diyala last week that that U.S. troops had arrested 10 Iraqi soldiers suspected of sectarian killings. There was no official U.S. comment.

Iraqi MP Muhammad al-Dayni appeared on al-Jazeera television to say that Brigadier al-Kaabi, leader of the fifth division in charge of Diyala province security, had led the arrest of 400 civilians. Hundreds of houses had been looted, he said. Al-Dayni accused the parties in power of supporting such acts, referring to the Shia parties in parliament.

The fighting has intensified now, but Baquba has long been a city of fierce resistance to the occupation. Resistance groups have often frustrated the efforts of the Multi-National Forces (MNF) and Iraqi security forces to bring the city under their control.

Residents of Baquba told IPS that an Iraqi police brigadier-general had used loudspeakers to announce dire warnings to residents.

"We were used to hearing our own government calling us terrorists, Saddamists and Zarqawis before, but this man added new words to the vocabulary like bastards and expressions of that sort," Abu Omar, a law student at Diyala University told IPS. "Yet we were not surprised because we know he was just repeating what his green zone masters have always said."

Mazin al-Zaidy, a resident of Baquba, told IPS that the situation in Diyala province could be the worst in Iraq because people of many ethnicities live in the area. "The MNF and militias concentrate on clearing it of the Arab Sunnis prior to any federalism plan."

Al-Zaidy said "there are Kurds, Shias and Sunnis who share the province, and that has to be altered for the benefit of the first two groups." Al-Zaidy was referring to the towns Mendily, Jalowlaa and surrounding areas that are marked Kurdish on the Kurdistan map.

The influence of each group changes often. "Each day I wake up I don't know who is in control of my city," said a religious sheikh in Baquba who asked to be referred to as Sheikh Ahmed. "One day it is the Americans, the next day a militia, the next day a resistance group."

Diyala province gets little media attention "because of the journalists' fear of going in," said al-Zaidy.

The new violence has ripped apart old traditions, he said. "The people of the province do not understand how these powers could turn it into a sectarian city from a wonderful 1,400 years of community peace and intermarriages."

The U.S. military has announced meanwhile that bomb attacks in Baghdad have hit an all-time high. The number of U.S. soldiers killed is now approaching the 3,000 mark.

The number of Iraqi casualties runs into hundreds of thousands.

Her remarks echoed those of Senate Armed Services Committee Chairman John Warner, R-Va., who last week said Congress should reconsider its options if the security situation - which he described as dire - does not improve in the next couple of months.

Warner is not up for re-election, while Snowe is, although she is considered a shoo-in.

As the Nov. 7 elections inch closer, more and more Republicans have grown louder in expressing their opposition to the White House's handling of the war, which remains unpopular with voters and a thorn in the side of Republicans struggling to maintain control of Congress.

Among those voicing their disappointment with the war are Republican Sens. Susan Collins of Maine and Chuck Hagel of Nebraska, along with Reps. Christopher Shays of Connecticut and Walter Jones of North Carolina.

"As conditions in Iraq continue to worsen, there must be no question among the administration, the Congress and the Iraqi unity government that staying the course is neither an option nor a plan," Snowe said Tuesday.

Last year, the Senate overwhelmingly passed a measure championed by Warner that labeled 2006 the year of transition in Iraq. But a spike in U.S. casualties and ethnic violence kept troop numbers high with no chance troops will return home in large numbers by the time voters head to the poll.

Police searched the man's apartment and confiscated a laptop and a number of computer discs. Prosecutors accused him of posting video and audio messages from Osama bin Laden and other major al-Qaida leaders on the Internet.

The Federal Prosecutor's Office has declined to give further details, saying the case was still ongoing.

The arrest comes as Germany is stepping up measures aimed at preventing people from using the Internet to promote terrorism.