Jerusalem (AFP) - An agent of Israel's Shin Bet security service has been killed by friendly fire on the Gaza border after being mistaken for a Palestinian attacker, the agency said.

Amir Maimoni, 29, was shot dead during an operation on Tuesday, Shin Bet chief Yoram Cohen said in an agency statement released late Wednesday.

"Regrettably a tragic operational development took place in the field during the mission," Cohen was quoted as saying at Maimoni's funeral, to which media were not admitted.

A fellow Shin Bet agent "misidentified and shot at Amir, hitting him," Cohen said. "All efforts to revive him failed."

No other details of the operation were provided.

Former service chief Avi Dichter said that such incidents were rare.

"I remember such a mishap 20-something years ago," he told Israeli public radio on Thursday.

"Every day and every night the Shin Bet's people... find themselves confronted with the enemy," he said.

"Under such tension, you depend at all time on the interpretation and professional analysis of each and every fighter, and sadly in this instance an incorrect interpretation led to this tragic mishap," he said.

Israeli news site Ynet said agents were operating along the Gaza border as part of efforts to combat activity by the strip's Islamist rulers Hamas, including the digging of tunnels into Israeli territory.