Chadian police on Friday dispersed two attempts to hold rallies by opposition parties calling for a boycott of upcoming elections in which President Idriss Deby Itno is expected to extend his 30-year rule.

The rallies were organised by Deby opponents Saleh Kebzabo and Succes Masra to call on Chadians to boycott the first round of the vote on April 11.

Dozens of heavily equipped riot police surrounded the home of Kebzabo, who recently withdrew his candidacy to protest against the "militarisation of the electoral campaign," an AFP journalist reported.

The head of the National Union for Development and Renewal party had wanted to hold the rally there.

Earlier, police dispersed supporters who had sought to challenge the ban on such gatherings put in place by the district's mayor.

Later in the day in front of the headquarters of Masra's The Transformers party, police deployed and fired tear gas, forcing a few dozen supporters to flee, the AFP journalist witnessed.

"We are surrounded at The Transformers party by police who are currently firing on supporters attending the rally to say no to a sixth term" for Deby, Masra told AFP by phone.

He said around 30 of his supporters had been arrested and two were "seriously" wounded in the eye and stomach.

It was not immediately possible to confirm his claims.

In the run up to the vote, the 68-year-old Deby has banned and violently put down peaceful marches for his ouster, with some of his potential challengers arrested, barred from the election or both.

Amnesty International has raised the alarm over restrictions on the right to peaceful assembly and "arbitrary arrests", while UN Secretary General Antonio Guterres deplored the use of force.

The vast desert country has become a key regional ally of the West in the fight against jihadists.

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