BAGHDAD, Iraq (CNN) -- Coalition forces found 26 bodies buried in mass graves and a bloodstained "torture complex," with chains hanging from walls and ceilings and a bed connected to an electrical system, the military said Wednesday.

Twenty-six bodies were found in mass graves near a "torture complex" discovered by coalition forces. more photos »

The troops made the discovery while conducting an operation north of Muqdadiya, Iraq.

From December 8 to 11, the troops who found the complex also killed 24 people they said were terrorists and detained 37 suspects, according to a statement issued by Multinational Division North at Camp Speicher in Tikrit.

The moves were part of an operation called Iron Reaper that has been in progress across northern Iraq for the past few weeks.

The complex was in an area thought to be an al Qaeda in Iraq haven and operating base, the military said. Iraqis had told the military about the site during an earlier operation.

"Evidence of murder, torture and intimidation against local villagers was found throughout the area," the military statement said.

Ground forces first found what appeared to be a detention facility, which was one of three connected to the torture complex, Multinational Division North said.

One of the facilities appeared to have been a headquarters building and a torture facility, it added.

As the area was cleared, the bodies were found.

Eventually, 26 bodies were uncovered in mass graves next to what were thought to be execution sites, the military said.

The bodies are believed to have been dead between six and eight months, according to a gruesome military video shot at the scene. Some had their hands tied behind their backs. Identification is proving to be a challenge because of advanced decomposition.

Photos given to the news media show a filthy bed wired to an electrical system, with an outlet hanging from wires on the wall. In the video, troops point out rubber hoses and boxing gloves, a ski mask and a blood-covered sword and knives. Other still photos show an entrance to the underground bunker and barbed wire stretched outside it.

A short distance away from the complex, troops found a bullet-riddled Iraqi police vehicle. Some of the bodies may belong to Iraqi police, according to the military video.

The operation netted nine weapons caches, which have been destroyed, the military said. They included anti-aircraft weapons, sniper rifles, more than 65 machine guns and pistols, 50 grenades and a surface-to-air missile launcher and platform, the statement said.

Also found were mines, pipe bombs, rocket-propelled grenades, mortar tubes and rounds and 130 pounds of homemade explosives. E-mail to a friend

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