Cairo, AP—A homemade bomb has exploded at an election rally for Egyptian presidential candidate Abdel-Fattah El-Sisi, wounding four people including two policemen, the official news agency reported.

Sisi, the front-runner in the May 26-27 vote, was not at the rally in the Cairo district of Ezbet El-Nakhl when the bomb went off late Saturday.

It was the first reported attack on a campaign event for the retired field marshal, who ousted Egypt’s first elected president last July. Sisi has not appeared in any election rallies, apparently for security reasons, restricting his campaign to television appearances and interviews.

Sisi said in a recent TV interview that two assassination plots against him had been uncovered, but he gave no details.

Islamic militants have stepped up attacks in Egypt since the ouster of Islamist president Mohamed Mursi. They have targeted senior government officials, security facilities and army and police personnel across much of the country.

Sisi’s only rival in the vote is leftist politician Hamdeen Sabahy, who has been crisscrossing the country to canvass voters.

Sabahy won nearly five million votes in the last presidential elections in 2012, finishing a strong third. Mursi won that election, but Sisi removed him a year later after millions staged street protests demanding he resign.

Mursi’s Muslim Brotherhood had won every vote since the February 2011 ouster of longtime autocrat Hosni Mubarak, although Mursi’s runoff win in June 2012 was narrow.

Sisi is expected to win comfortably, but his repeated calls on Egypt’s 50 million-plus voters to participate indicate he seeks a strong mandate for the next four years.

A constitution drafted by a mostly secular panel appointed by the military-backed interim president was adopted in a nationwide referendum in January by more than 90 percent, but turnout was relatively low at under 40 percent.

In a separate development, a court in the Nile Delta city of Kafr El-Sheikh on Sunday convicted 126 alleged Mursi supporters of assaulting police, damaging public property and inciting violence last summer, sentencing them each to 10 years in jail.

The verdict was the latest in a series over recent months that has seen hundreds of Mursi supporters sentenced to death or imprisoned. In some cases the verdicts were announced after no more than two hearings.

Prosecutors have said the 126 defendants committed the crimes on August 16, two days after security forces moved to end two sit-in protests by Mursi supporters in Cairo, killing hundreds.