Two bomb attacks on Saturday that appeared to target a peace rally by leftist and Kurdish activists in Turkey's capital, Ankara, killed at least 95 people and injured almost 200 others, Turkey's Interior Ministry said.

The explosions occurred minutes apart outside Ankara's main train station as hundreds of people were gathering for the rally, organized by the country's public sector workers' trade union and other civic society groups. The rally aimed to call for increased democracy and an end to the renewed violence between Kurdish rebels and Turkish security forces.

There were no claims of responsibility for the attack, which came at a tense time for the NATO-member country, which will hold a general election on Nov. 1. Authorities said they were investigating whether the attacks — which hit some 50 yards apart from each other — were suicide bombings.

Prime Minister Ahmet Davutoglu said there were "strong signs" that the attacks were suicide bombings and suggested that Kurdish rebels or Islamic State in Iraq and the Levant (ISIL) fighters could be behind them. He held an emergency security meeting to discuss the attack, and his office said he was suspending his election campaign programs for the next three days.

Hours after the bombing, the outlawed Kurdistan Workers' Party (PKK) ordered its fighters to halt operations in Turkey unless they faced attack. The group said through the Firat news agency website that it would avoid acts that could hinder a "fair and just election.”

At a news conference, Davutoglu declared a three-day official mourning period for the victims as well as for all those killed in terror attacks since July.

The Turkish government also imposed a temporary news blackout covering images that showed the moment of the blasts, gruesome or bloody pictures or "images that create a feeling of panic." A government spokesman warned media organizations they could face a "full blackout" if they did not comply.

Many people in Ankara reported being unable to access Twitter and other social media websites after the blasts. It was not clear if authorities had blocked access to the websites, but Turkey often does impose blackouts following attacks.

Television footage from Turkey's Dogan news agency showed a line of protesters fanned out on the street near the train station, chanting and performing a traditional dance with their hands locked, when a large explosion hit behind them.

The video also showed several people later lying injured on the streets or being taken into ambulances. Scuffles broke out between police and people frantically searching for loved ones or complaining about poor police response.

Small anti-government protests broke out at the scene of the explosions and outside of hospitals as Interior Minister Selami Altinok visited. Demonstrators shouted "police murderers!" at the scene of the blasts. Many were dispersed as the security forces intervened.

Faruk Bildirici, a Turkish journalist who was attending the rally, told Al Jazeera that he was only a few feet away from the explosions and that they had occurred within minutes of each other.

"Some people were crying and shouting out condemning the attack, some —particularly members of the Turkish Medical Association — were trying to help the wounded," Bildirici said.

"I have seen people using banners trying to cover dead bodies and striving to carry the wounded, again with large banners ... This gathering was to deliver a message of peace, democracy and brotherhood in Turkey. This attack prevented people from delivering this message."

Authorities had been on alert after Turkey agreed to take a more active role in the U.S.-led battle against ISIL, opening up its bases to U.S. aircraft to launch air raids on the group in Syria and carrying out a limited number of strikes on the group.

Turkish President Recep Tayip Erdogan condemned the attacks, which he said targeted the country's unity and peace, and called for solidarity.

"The greatest and most meaningful response to this attack is the solidarity and determination we will show against it," Erdogan said.

Washington also condemned the attack and reiterated its allegiance with Ankara.

"The United States will continue to stand side by side with the Turkish government and people as together we take on the scourge of terrorism," U.S. National Security Council spokesman Ned Price said.

Critics have accused Erdogan of reigniting the fighting with the Kurds for electoral gains in the hope that the turmoil would rally nationalist votes around the ruling Justice and Development Party, or AKP. Electoral gains by the country's pro-Kurdish People’s Democratic Party (HDP) caused AKP, founded by Erdogan, to lose its parliamentary majority in an election in June, following a decade of single-party rule. Erdogan denies the accusation.

Saturday’s was the third attack targeting meetings of Kurdish activists. In July, a suicide bombing blamed on ISIL killed 33 peace activists, including many Kurds, in the town of Suruc near Turkey's border with Syria. Two people were killed in June in a bomb attack at an HDP election rally.

"This attack resembles and is a continuation of the Diyarbakir and Suruc" attacks, said Selahattin Demirtas, leader of the HDP. "We are faced with a huge massacre."

Al Jazeera and wire services