"We have seen once more ... that the PKK is a bloody organisation and does not hesitate to kill the people it says it is fighting for," he said. "The PKK acts according to the demands of global powers, not ... the people in the region."
Prime Minister Binali Yildirim cancelled his day's schedule and was heading to Elazig with Isik and General Hulusi Akar, head of the armed forces, sources at Yildirim's office said.
The provincial governor's office said 14 of the wounded were in serious condition.
The PKK has carried out dozens of attacks on police and military posts since 2015 in the largely Kurdish southeast in its fight for greater autonomy for Turkey's 15 million Kurds.
But Elazig, a conservative province that votes in large numbers for the ruling AK Party, had been spared violence until now.
Video footage showed a plume of black smoke rising above the city after the blast, which uprooted trees and gouged a large crater outside the police complex, located on a busy thoroughfare in the city of 420,000 people.
In Van province, further east, two police officers and one civilian were killed and 73 people were wounded late on Wednesday when a car bomb exploded near a police station, the local governor's office said in a statement.
There was also no claim of responsibility for the attack in Van, a largely Kurdish province on the Iranian border. The Van governor's office said the PKK was responsible.
The south-east has been scorched by violence since a two-and-a-half-year ceasefire with the PKK collapsed in July last year. Thousands of militants and hundreds of soldiers and police officers have been killed, according to official figures.
Rights groups say about 400 civilians have also been killed.
More than 40,000 people have been killed in violence since the PKK first took up arms in 1984.
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