DODOMA, Tanzania (AP) — Tanzania’s main opposition parties failed to form a coalition Tuesday, dashing hopes of teaming up to defeat the longtime ruling party in the October presidential election.

The national electoral commission said the CHADEMA party’s Tundu Lissu, ACT Wazalendo’s Bernard Membe and NCCR Mageuzi’s Yeremia Maganja will independently challenge President John Magufuli, who seeks a second five-year term.

In Tanzania, whoever gets the most votes wins the election outright. Those pursuing a united opposition had called it the best chance at an upset.

Lissu, who recently returned from exile in Belgium, told reporters that the opposition parties were still deliberating on how to cooperate. “We’re still in talks,” he said, without giving details.

Membe blamed Tanzania’s election laws, which require that political parties seeking to form a coalition must present a detailed plan to the registrar of political parties. “There was no sufficient time for political parties to meet and make such decisions,” the former foreign minister said.

After taking office in 2015, Magufuli barred opposition groups from political gatherings. Since then, some opposition figures have been arrested for their engagement in political affairs.

Membe on Tuesday accused the government of allowing violence against opposition candidates.

Opposition parties, human rights groups and others have criticized the restrictions as an example of the stifling of dissent under Magufuli’s administration. Amnesty International has warned that the October election will take place in a climate of fear as restrictions tighten.

Magufuli won the 2015 election with 58% of the vote.