Israeli troops killed a 65-year-old Palestinian in his bedroom on Friday during a pre-dawn raid to seize a Hamas suspect who lived in the same building in what the army admitted was a mistake.

The man was shot as troops swooped on houses in the occupied West Bank to re-arrest five members of the Islamist Hamas group who had been freed from Palestinian jails just the day before.

During the operation they broke into the home of Amr Qawasme, one floor above a Hamas militant, and stormed into his bedroom, local residents said. The man's wife, Sobheye, said she heard several shots fired and later saw her husband lying in a pool of blood.

"I was praying when they entered. I do not know how they opened the door. They put their hand to my mouth and a rifle to my head," she told Reuters after Qawasme's body was removed.

"I was shocked. They did not allow me to talk. I asked them, 'What did you do?' They asked me to shut up."

Reuters Television video showed Qawasme had been shot in the head and body. Bullet casings were scattered on the floor of his room, his pillow and mattress left soaked with blood.

A statement by the Israel Defence Forces said soldiers who went to arrest Wael Mahmoud Said Bitar -- who it said had helped plan a 2008 suicide bomb attack in which an Israeli woman was killed -- had killed a man in the house during the raid.

"The IDF regrets the outcome of the incident," it said. An investigation was ordered and conclusions expected next week.

DEADLY WEEK

Violence in the occupied West Bank has largely tapered off in the past few years as a result of security measures by Israel and a bolstered Palestinian police force supervised by Western-backed Palestinian President Mahmoud Abbas's government.

But the past week has seen a rise in tensions.

Last Friday, a Palestinian woman died following a protest against an Israeli barrier built across the West Bank. A local medic said the woman died after inhaling teargas.

On Sunday, an Israeli solider shot dead a Palestinian who approached a West Bank checkpoint holding a glass bottle.

Israel and Abbas's administration have a common foe in Hamas, which rejects Middle East peace efforts and controls the Gaza Strip coastal enclave.

But the Israelis sometimes chafe at Abbas's handling of the group, and were clearly irked by the Palestinian Authority's decision to release the six Hamas militants on Thursday.

A Palestinian source said the men were originally detained for threatening national security interests. Israeli media said the militants, who had been on hunger strike, were freed at the request of the emir of Qatar.

Five of the men were from Hebron, and one of them, Wael Bitar, lived one storey below the victim, residents said. They were all seized by the Israeli troops overnight.

"Hamas holds the Palestinian Authority in the West Bank responsible with the occupation for the crime, spokesman Sami Abu Zuhri said in Gaza.

"We demand an end to arrests and torture and we demand that the Palestinian Authority lift restrictions so that resistance fighters can respond to crimes by the occupiers."

Several hundred Hamas followers have been rounded up by Abbas' forces since the Palestinian split in 2007. Hamas in Gaza has retaliated against members of Abbas's Fatah movement.

(Additional reporting by Nidal al-Mughrabi) (Writing by Dan Williams and Douglas Hamilton; editing by Crispian Balmer and Noah Barkin)