Among the Hamas leaders were seven Cabinet officials, including Deputy Prime Minister Nasser Shaer and Religious Affairs Minister Nayef Rajoub, and 21 members of the Palestinian parliament, according to the Palestinian Liberation Organization.
The arrests took place four days after Palestinian militants kidnapped Israeli soldier Gilad Shalit. The Israeli government said at the time that it held Hamas responsible for the kidnapping.
The Israeli Army has launched limited military raids against Palestinian targets in Southern Gaza in response to the kidnapping and on Thursday delayed a planned ground invasion of northern Gaza.
Mark Regev, the spokesman for the Israeli Foreign Ministry, indicated that the captured Palestinians were not meant as a bargaining tool for Shalit's release. The government had previously rejected demands to free Palestinian prisoners in exchange for Shalit.
"The arrests of these Hamas officials ... is part of a campaign against a terrorist organization that has escalated its war of terror against Israeli civilians," he said.
Chief Palestinian negotiator, Saeb Erkat, a political ally of President Mahmoud Abbas, criticized the arrests.
"We have no government, we have nothing. They have all been taken," Erkat said. "This is absolutely unacceptable and we demand their release immediately."
In addition to the arrests, Israeli forces bombed Hamas training camps and knocked out Gaza's main power plant, all in an attempt to force the release of Shalit.
Abbas called the incursion "a crime against humanity."
In a separate incident, Israeli soldiers near Ramallah found the body of 18-year-old West Bank settler Eliahu Asheri. He was taken captive Sunday, and his captors of the Popular Resistance Committees pledged on Wednesday to kill Asheri if the Israeli incursion into Gaza continued.
Israeli officials believe that Asheri had been killed prior to the PRC's ultimatum. The PRC is also one of the militant wings believed to be holding Shalit hostage.
Asheri was laid to rest Thursday afternoon in his home settlement in Itamar.
