Egypt’s former intelligence chief, Omar Suleiman, died from a rare disease affecting the heart and kidneys, the U.S. clinic where he was undergoing medical tests at the time said on Friday.

Suleiman, who died at age 76 on Thursday, was former Egyptian president Hosni Mubarak’s last deputy and one of his most trusted advisers. He stepped briefly into the limelight when he was made vice president days before Mubarak was ousted in a popular uprising last year.

“On Thursday, July 19, General Omar Suleiman … passed away due to complications from amyloidosis, a disease that affects multiple organs including the heart and kidneys,” the Cleveland Clinic said in a statement quoted by Reuters.

The statement said Suleiman had checked into the clinic on Monday and the disease was discovered after her underwent multiple tests.

Meanwhile, the Egyptian daily Al-Masry Al-Youm reported on Friday that Suleiman’s body is expected to arrive in Cairo on Saturday morning after being delayed due to procedures in the U.S.

Suleiman’s body will be accompanied from America by his daughters, the report said, and his funeral will be held at Aal Rashdan Mosque in Nasr City at dawn Saturday.

Cairo International Airport authorities have implemented tight security measures, the report noted, including setting up checkpoints on streets leading to the airport, deploying greater numbers of plainclothes and uniformed security personnel and increasing security at the entrances and exits of various halls.

Former Minister of Defense, MK Binyamin Ben Eliezer (Labor), expressed his sorrow over Suleiman’s death, calling him “an important leader who contributed much to the security and strength of Egypt.”

“In his extensive activity, his personality and his trustworthiness, Suleiman made a meaningful contribution to stability in the Middle East,” said Ben Eliezer. “He has a meaningful contribution to the maintenance of the peace treaty between Israel and Egypt and to its being honored. I will miss him.”

A few months ago, Suleiman joined the race for the president of Egypt. He was disqualified, however, by Egypt’s election commission because he fell short of the required number of public endorsements.

Suleiman also warned against a win in the presidential race by the Muslim Brotherhood, saying he feared Israel will have to invade the Sinai Peninsula if the Muslim Brotherhood ends up winning the presidential election.

“I fear that incorrect judgments will push us into confrontations with Israel,” he said. “The Sinai may become an area from which rockets are fired into Israel and the parties may be drawn into war.”

The Muslim Brotherhood’s candidate, Mohammed Morsi, ended up winning the presidential election. He was sworn in last month.