DIYARBAKIR, Turkey (Reuters) - Explosions and gunfire resounded around the southeastern Turkish town of Cizre on Friday after a clash overnight that the army said killed six Kurdish militants and one soldier, as a security operation there entered its 11th day.

Since a two-year ceasefire between Kurdistan Workers Party (PKK) militants and Ankara fell apart in July, the mainly Kurdish southeast has been plunged back into a three-decades-old conflict which has killed more than 40,000 people.

A helicopter clattered overhead and armored vehicles sped along a hilltop road above Cizre, near the Syrian border, as security forces pressed on with a campaign across the region involving thousands of troops, backed by tanks.

Reuters TV footage showed smoke billowing from buildings hit by blasts, while streets were empty and shops shuttered.

The town, in Sirnak province, is the focus of what the government has described as an operation to “cleanse” the area of militants. But locals dispute that description and complain that the attacks are indiscriminate.

“The recent war being conducted in the Sirnak area, especially in Cizre, is not a cleansing. They are shelling randomly,” said shopkeeper Abdullah Varkin, 38, speaking as a small group of children and men looked on.

“The people are miserable. The sick cannot even go to hospital. The wounded are trying to treat themselves at home and some died due to a lack of doctors and blood loss,” he said.

Locals also complained about a lack of food and water.

FULL CURFEWS

Both Cizre and Silopi, 30 km (19 miles) away near the Iraqi border, have witnessed intense fighting since a round-the-clock curfew was declared in both towns 12 days ago.

Three soldiers were wounded in Thursday evening’s firefight and one of them died in hospital, the army said in a statement.

In the town of Sirnak, security sources said four students and two staff suffered burns and smoke inhalation when PKK militants, their faces hidden by scarves, threw petrol bombs in a state-run cultural center on Friday, triggering a fire.

They said a gunfight erupted between security forces and militants as the building was evacuated.

State media say 168 PKK militants have been killed in the latest security operations. The pro-Kurdish Peoples’ Democratic Party (HDP) says at least 38 civilians have been killed.

The body of Taybet Inan, a 57-year-old mother of 11 shot dead by security forces last week, was left lying on a street in Silopi for a week before being retrieved on Friday, said HDP lawmaker Ferhat Encu. Snipers killed her brother-in-law and wounded her husband when they sought to retrieve the body.

Many parts of Silopi were without electricity, and dozens of people were sheltering in the basements of houses, the HDP said.

Since the PKK launched its insurgency in 1984, fighting has been largely focused in the countryside, but the latest conflict has been focused in urban areas, where the PKK youth wing has set up barricades and dug trenches to keep security forces out.

The PKK is designated a terrorist group by Turkey, the United States and the European Union. Ankara launched a peace process with the group’s jailed leader Abdullah Ocalan in late 2012 but the talks ground to a halt early this year.