* Senior member of Hamas security service held since Sept. 13
* Egypt has supported Israeli efforts to isolate Gaza
(Adds Egyptian security official's comment paragraphs 4-5)
GAZA, Sept 24 (Reuters) - Egypt freed on Friday a top Hamas security official after holding him for 10 days on what Cairo media described as allegations of involvement in smuggling to the Gaza Strip and the killing of an Egyptian border guard.
Hamas, the Islamist group that runs Gaza, said Mohammed Dababesh had returned to the Palestinian territory.
"The release came as a result of contacts between the Hamas leadership and Egypt. It was also proof that the reported allegations were false and incorrect," said Hamas spokesman Sami Abu Zuhri.
An Egyptian security official in Cairo confirmed there were no grounds for continuing to hold the Hamas official.
"Dababesh was released after it was made certain he is not involved in any matters harming Egyptian security. No charges were filed against him," said the official, who declined to be named.
Dababesh, a senior member of Hamas's internal security service, was detained on Sept. 13 upon landing in Cairo airport from Saudi Arabia.
Egypt is one of two Arab states to have a peace accord with Israel and has supported the Jewish state's efforts to isolate Gaza. The Egyptian-Gaza border is tightly controlled to prevent smuggling from the Sinai desert.
Cairo has also tried, without success, to heal a violent schism between Hamas and the U.S.-backed government of Palestinian President Mahmoud Abbas, which holds sway in the Israeli-occupied West Bank.
Abu Zuhri said at least 40 members of Hamas and other Palestinian factions remained in Egyptian custody, and called for them to be freed too.
"We hope that the (Dababesh) release will be the first step toward righting relations between Hamas and the Egyptian leadership and bringing an end to detention of Palestinians in their jails," he said. (Reporting by Nidal al-Mughrabi, additional reporting by Dina Zayed in Cairo; Editing by Noah Barkin)
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