The International Red Cross called on Hamas on Thursday to provide proof that Israeli soldier Gilad Shalit is still alive nearly five years after his capture by Palestinian militants.

In an unusual public appeal, the independent aid agency said Shalit's family had a right under international humanitarian law to be in contact with their 24-year-old son, held incommunicado since his capture on June 25, 2006.

"Because there has been no sign of life from Mr. Shalit for almost two years, the ICRC is now demanding that Hamas prove that he is alive," the Geneva-based International Committee of the Red Cross (ICRC) said.

The ICRC, which visits detainees worldwide, also reiterated its long-standing request to visit Shalit in custody.

Hamas-led gunmen tunnelled from Gaza into Israel to seize Shalit, who has been held at an unknown location in Gaza ever since. The last sign of life was a videotape released by his captors in September 2009 showing Shalit, pale and thin, pleading for his life.

"The total absence of information concerning Mr. Shalit is completely unacceptable," ICRC Director-General Yves Daccord said in a statement.

He has become a compelling symbol for Israelis, many of whom do compulsory military service and identify with his plight.

The ICRC has called repeatedly but unsuccessfully on the militant Islamist group to allow Shalit to exchange family news with his loved ones and to receive visits by ICRC officials.

HUMANE TREATMENT

Shalit is not considered a prisoner of war, as he was seized by an armed group rather than by forces of a state that has ratified the Third Geneva Convention. However, like all other detainees captured in conflict, he is entitled to humane treatment under the Geneva Conventions, according to the ICRC.

"Hamas has an obligation under international humanitarian law to protect Mr. Shalit's life, to treat him humanely and to let him have contact with his family," Daccord said.

His parents, Noam and Aviva, are in close contact with the ICRC and have come to its headquarters for talks over the years.

On Friday, the fifth anniversary of his capture, the parents have said they will spend the day in a tent plastered with signs urging Israeli leaders to bring their son home.

They have led a campaign to press Israeli Prime Minister Benjamin Netanyahu to agree to a prisoner swap with Hamas.

Netanyahu has said he is committed to seeking Shalit's release. But his rightist government balks at meeting Hamas' demands to free hundreds of prisoners, among them men convicted of lethal attacks, calling it too great a security risk.

Ismail Haniyeh, head of the Hamas administration in Gaza, asked by reporters on Wednesday about the 5th anniversary of Shalit's capture, said: "The Palestinian resistance has some demands, and it is sticking with its demands."

The ICRC also urged Israel to allow relatives of Palestinian detainees from Gaza to visit them in custody in Israel.

The Jewish state suspended visits in June 2007 in a move which the ICRC said contravened international humanitarian law and had prevented more than 700 families from seeing their detained relatives over the past four years.

"The International Committee of the Red Cross urges Israel, on humanitarian grounds, to lift the suspension of family visits for all detainees from Gaza," it said in a separate statement issued earlier on Thursday.