BAKU, Azerbaijan (AP) _ Prime Minister Ilham Aliev pledged Monday that this week's presidential election will be free and fair, warning that authorities will deal sternly with anyone who resorts to violence.

The New York-based Human Rights Watch said Monday that the presidential campaign had been manipulated to favor Aliev, who is seeking to succeed his ailing father Geidar Aliev. The 80-year-old leader appointed his son prime minister in August after dropping out of the race for health reasons.

The group said election commissions were stacked with Aliev's supporters and non-governmental organizations were prevented from monitoring the vote.

It also accused officials of obstructing opposition rallies and said police had detained and beaten hundreds of opposition activists.

``The direct result of the government-sponsored campaign against the opposition is that ... elections in Azerbaijan will be of questionable legitimacy, regardless of the fairness and transparency of the election-day procedures,'' Human Rights Watch said.

Voters in this oil-rich Caspian Sea coast nation will decide Wednesday on a successor to Aliev's father who has ruled for the last decade since taking power after a military coup.

Aliev told a news conference that election rules and procedures had been established to make falsification impossible.

``These elections will be held democratically ... they will be transparent and free,'' Aliev said, adding that ``if someone wants to destabilize the situation, he will get a corresponding response. We will not allow a riot or military coup.''

Also Monday, two members of a pro-government party suffered second and third-degree burns after setting themselves on fire outside the Central Election Commission headquarters in Baku to protest against opposition candidate Isa Gambar's participation in the race.