Twin bomb attacks have hit the regional headquarters of Turkey's main pro-Kurdish party in two cities, injuring more than half a dozen people and escalating tensions ahead of June 7 legislative elections.
Six people were injured, three of them seriously, in the blast caused by a suspect parcel at the office of the People's Democratic Party (HDP) in the southern city of Adana, a party official said.
A bouquet of flowers sent to the party's office in the nearby city of Mersin also exploded, the official said.
Video footage showed several people with bloodied faces.
The government immediately condemned the bombings, with Prime Minister Ahmet Davutoglu pledging to bring the perpetrators to justice.
"I strongly condemn this attack," Davutoglu told a rally in the city of Karaman in central Turkey.
Davutoglu said he gave a "clear instruction" for a full-scale investigation.
But he warned against any smear campaign to discredit his ruling party after some HDP figures blamed the government for the attacks.
"We have stood against violence since the very beginning. God willing, we will march into June 7 in peace," he said.
In a public rally in the Black Sea city of Samsun, President Recep Tayyip Erdogan lambasted the HDP for its links to the outlawed Kurdistan Workers' Party (PKK) which has waged an armed insurgency in the southeast for Kurdish autonomy.
He urged voters to steer clear of the party in the polls.
"I am appealing to all of Turkey: Turks, Kurds, Arabs, Circassians, Abkhazians - whoever comes to mind - will 78 million of you give the right response to the political organisation that is guided by a terrorist group?" he
Hundreds of HDP supporters, chanting slogans like "No to Fascism!", meanwhile marched down Istanbul's central Istiklal Street late on Monday in solidarity with the HDP after the attacks, a photographer for the AFP news agency reported.
In defiance of the attacks, the HDP's co-chairman Selahattin Demirtas went ahead with a planned rally in Mersin on Monday evening, launching stinging broadsides against Erdogan, whom he accuses of supporting the Islamic State of Iraq and the Levant.
"The president of the country calls the HDP a terrorist organisation but doesn't say a word to [ISIL]," Demirtas said.
"Those who cooperate with a rapist gang cannot give us democracy lessons."
The attacks were the latest in a string of violence against HDP targets in the run-up to an increasingly tense election.
In April, unidentified assailants opened fire on the HDP headquarters in the capital Ankara, with no casualties.
The government condemned that attack as a blow to Turkey's democracy and stability.
The HDP is seeking in the election to clear the 10 percent quota to take seats in the parliament.
Its success could dent the ruling AKP party's plans to reach a thumping majority in the 550-seat parliament in order to change the constitution and create a presidential system.
Demirtas told Erdogan after the attacks: "We received your message. We still will not make you president."
Deputy Prime Minister Yalcin Akdogan said earlier this month it would be "super" if the HDP failed to clear the 10 percent threshold.