JOHANNESBURG (AP) — Former President Jacob Zuma threatened Saturday to take legal action seeking to stop the announcement of South Africa’s election results as scheduled Sunday, demanding that allegations of vote-rigging made by his party be addressed first.

Zuma spoke after his party announced that it was seeking a re-run of the elections, saying it had submitted evidence to the Independent Electoral Commission proving its allegations of widespread irregularities.

Zuma’s uMkhonto weSizwe Party has emerged as the third biggest political party, with 99% of the votes counted in South Africa’s highly contested election. The governing African National Congress lost its parliamentary majority for the first time since it came into power after the end of apartheid in 1994.

Zuma did not elaborate on the details and nature of the vote-rigging allegations, but his party’s officials said they include allegations that the electoral body’s IT system had been tampered with when it had technical glitches Saturday.