A spokeswoman for protesters who defied a blockade of Gaza by entering by sea said one was arrested after returning to Israel by land. Angela Godfrey-Goldstein said that Jeff Halper, an Israeli citizen, was detained by police after he passed through the Erez crossing. Police spokesman Micky Rosenfeld said Halper was taken to a police station in southern Israel Tuesday. He had no details. Minnesota-born Halper was among dozens of international activists who sailed into Gaza on Saturday to protest the Israeli blockade, imposed after the violently anti-Israel Hamas movement took control there last year. The others are to sail for Cyprus Thursday.