Two people died and more than 100 were injured after two explosions rocked a Kurdish party election rally in southeast Turkey on Friday, the country's Agriculture Minister Mehdi Eker said.

The blasts occurred five minutes apart at the pro-Kurdish People's Democratic Party, or HDP, final election rally as party leader Selahattin Demirtas was preparing to address the crowd in Diyarbakir, the main city in Turkey's predominantly Kurdish southeast.

It wasn't immediately clear how many of the injured were seriously hurt. Health Minister Mehmet Muezzinoglu had earlier said around 50 people were injured in the incident and 20 to 24 of them were being treated in hospitals.

Rally organizers first said a malfunctioning power distribution unit caused the explosions, but Energy Minister Taner Yildiz later dismissed that. He said they were caused by an "external interference" with the power unit, though he did not say whether he believed a bomb was involved.

The explosions come at a tense time, two days before Sunday's parliamentary elections in Turkey, in which the Kurdish votes will be critical.

The party is vying to pass the threshold of 10 percent of total votes required to take seats in parliament. If it succeeds, it could make it impossible for the ruling AKP to reach a supermajority in parliament. That would scuttle the AKP's ambitions to introduce a new constitution and change Turkey's parliamentary system into a presidential system that could give President Recep Tayyip Erdogan executive powers.

Prime Minister Ahmet Davutoglu said authorities would investigate the cause of the explosions.

"Whatever is behind this incident -- whether it was a power transformer explosion, an assassination attempt, an act of provocation -- we shall investigate it," he said. "I call on my brothers in Diyarbakir: Please beware of exploitation of the incident and provocations. No one should be involved in provocations."

The rally was cancelled but a large group of youths remained at the site, protesting the explosions. Some threw stones at a police water cannon that moved in to disperse the crowd.

Demirtas urged calm.

"Whatever the cause, I invite the people to retain their common sense," Demirtas told CNN-Turk television by telephone. "Whatever happens, Turkey is in need of peace."

Demirtas said some of the injured lost limbs.

Earlier this week, assailants fired on a HDP campaign vehicle, killing its driver. Last month, bombs at two local HDP offices injured six people in southern Adana and in neighboring Mersin.