(CNN) -- Ten candidates, including the leader of the Muslim Brotherhood and a former spy chief, have lost their appeal against disqualification from upcoming presidential elections in Egypt, according to official news agency egynews.
The Supreme Presidential Electoral Commission (SPEC) said Tuesday it endorsed a previous decision to exclude 10 of 23 candidates from the contest scheduled for May 23 and 24 due to "legal irregularities."
Omar Suleiman, the most controversial candidate, was disqualified because "he did not collect the 30,000 endorsements from 15 different directorates in Egypt but obtained them from several cities only, which is not legal," the head of Egypt's executive election committee, Hatem Bagato, said on Saturday.
The candidates lodged appeals against the decision on Sunday.
Suleiman was head of Egypt's intelligence services and served as vice president under President Hosni Mubarak before his ouster. Last week, the Muslim Brotherhood called for a "million-man" protest in Cairo's Tahrir Square against the nomination of former members of Mubarak's regime.
Khairat el-Shater, the Brotherhood's preferred candidate, and Ayman Nour, the head of the Al Ghad party, also had their bans upheld due to issues surrounding unresolved pardons for time spent in prison under the Mubarak regime, the election committee said.
The other disqualified candidates included Hazem Abu Ismael, Mamdouh Outb, Ashraf Barouma, Hossam Khairat, Ibrahim Ghareeb, Ahmed Awad and Mortada Mansour, Bagato told CNN.
El-Shater -- a multi-millionaire businessman -- was jailed for five years by a military court during a crackdown on Islamist movements in the mid-1990s. In 2007, he was charged with providing funds and weapons to college students and imprisoned again.
He was still behind bars when the regime fell in February 2011, and the military junta that took power from Mubarak released him for medical reasons a month later. A subsequent pardon was challenged in court by the ruling Supreme Council of the Armed Forces.
He responded to Tuesday's decision by called on Egyptians to "protect the revolution," warning that plans for electoral fraud and vote-buying were under way, egynews reported.
Also Tuesday, the Muslim Brotherhood announced it was submitting another candidate, Mohammed Mursi, should el-Shater's appeal ban stand, Reuters.com said.
Hamdi Alkhshali contributed to this report.