DODOMA, Tanzania (AP) — Tanzania’s main opposition parties are alleging sabotage by authorities after dozens of candidates for parliament were disqualified for the October elections.

The CHADEMA party asserted that at least 57 of its candidates for parliament had been dubiously disqualified to clear the way for ruling party candidates. Parliament has 264 directly elected members.

“This is unacceptable, and we demand the national electoral commission to play fairly and reinstate our candidates,” said CHADEMA’s presidential candidate, Tundu Lissu.

The party also asserted that some 600 other candidates for local council posts were disqualified.

Another main opposition party, ACT Wazalendo, asserted that some of its candidates had faced unfair treatment.

The electoral commission said the ruling CCM party has won 18 legislative seats unopposed, and it rejected the opposition allegations.

“The NEC does not operate in favor of any political party or individual,” director Wilson Charles told reporters.

A total of 29 million Tanzanians are registered to vote in the Oct. 28 elections, in which President John Magufuli seeks a second five-year term.

After taking office in 2015, Magufuli barred opposition groups from political gatherings, and human rights groups have warned that such obstacles will increase ahead of the October vote.

The main opposition parties earlier this week failed to team up behind a single presidential candidate. 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.