Thomas Sutherland, a former agriculture professor who was swept up in an international drama when he was kidnapped by Islamic militants in Lebanon in 1985 and held for more than six years, died on Friday at his home in Fort Collins, Colo. He was 85.

His wife, Jean, said the cause had not been determined, though he had a heart condition.

Mr. Sutherland was among dozens of Westerners taken hostage in Beirut in the 1980s at the height of Lebanon’s civil war. When he was kidnapped, he was the dean of agriculture at the American University of Beirut.

After he was snatched near his Beirut home, where he lived with his wife, Mr. Sutherland was confined in a series of rooms, often blindfolded and chained to a wall, by gun-toting men who operated under Hezbollah, the Lebanese militant group.

The Western hostages were abused regularly, hit with fists, sticks and rifle butts, said Terry Anderson, the longest-held American, who was a Middle East reporter for The Associated Press. Mr. Anderson said he and Mr. Sutherland had spent a great deal of time together, lying side by side on cots and engaged in conversation.