Zimbabwean President Emmerson Mnangagwa survived a blast at a ruling ZANU-PF party rally Saturday, his spokesman said, adding that he had been taken to safety after the incident.
An AFP correspondent at the scene reported multiple injuries but could not immediately give a precise toll.
Images broadcast on Zimbabwean TV showed scenes of chaos and medics fighting to save those wounded by the blast at the White City stadium in the country's second city Bulawayo.
"The president was evacuated successfully. He is at state house in Bulawayo," said Mnangagwa's spokesman George Charamba.
"We suspect it's an explosion, certainly it was close to the VVIP stage."
Mnangagwa had been in the city to campaign for votes ahead of nationwide elections due on July 30.
They are the first polls since veteran leader Robert Mugabe was ousted following a brief military takeover in November last year, after 37 years in power.
It will be a key test for Mnangagwa, who succeeded the long-serving autocrat Mugabe seven months ago, and remains untested at the ballot box.
He has pledged to hold free and fair elections as he seeks to mend international relations.