"It is clear that these arrest operations are a new series of harsh attacks targeting Palestinian people." he said.
"If Hamas and other terrorist groups did not attack Israel there would not have been any destruction"
Yaweh420, West Coast, US
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"These actions will not help in stabilising the area or succeeding in what the [Palestinian] government seeks to reach - a comprehensive truce with Israel."
Shaer's wife said soldiers knocked on the door of their home in the West Bank city of Nablus and took him away. They also seized Shaer's computer, she said.
Soldiers also arrested Abdel Rahman Zeidan, a former cabinet minister, legislators Hamed Bitawi and Daoud Abu Ser, the mayors of the towns of Nablus, Qalqiliya and Beita - Adli Yaish, Wajih Qawas and Arab Shurafa - as well as the head of the main Islamic charity in Nablus, Fayad al-Arba.
"Arrests are better than shooting," Amir Peretz, the Israeli defence minister, said on Israeli Army Radio.
"The arrest of these Hamas leaders sends a message to the military organizations that we demand that this firing [of rockets] stop."
Troops also searched for Ahmed Haj Ali, a Hamas legislator in Nablus, but did not find him at home, neighbours said.
Thursday morning's roundup came hours after Israeli planes struck what the military said were money changing offices and other businesses in Gaza which were channeling funds to Hamas.
Three people were slightly wounded in one of the attacks, medical officials said, and four stores were damaged in another, Palestinian security officials said.
Electricity was cut off in parts of the town. A third airstrike in Gaza after midnight hit a car whose passengers escaped before the missiles landed.
More than 40 Palestinians have been killed in such missile attacks in the past week.
Last summer, Israel arrested scores of senior Hamas members in retaliation for the capture of Gilad Shalit, an Israeli soldier, by Hamas-allied fighters.
Shalit has not yet been released.