Taliban fighters have captured a district centre in Afghanistan's western province of Farah bordering Iran, where they have battled government security forces fiercely in recent months, officials said on Monday.
Naser Mehri, a spokesman for the provincial governor, said a large group of fighters had captured the centre of Anar Dara district on Sunday night after hours of fighting, though police and intelligence service forces were still holding out in their headquarters.
The Taliban released pictures that appeared to show fighters in the town, where skirmishes were taking place on Monday. Taliban spokesman Qari Yousuf Ahmadi said 15 policemen had been killed and several military vehicles seized, along with a large quantity of ammunition.
The announcement came days after local officials said the Taliban had inflicted heavy losses on Afghan special forces in another district of Farah, a poor and isolated region where the government has long struggled to impose control.
The pressure on Farah has grown as US air strikes and Afghan army operations have inflicted heavy casualties on Taliban fighters in neighbouring Helmand province, the main opium region in Afghanistan and a heartland of the insurgency.
Afghan and US commanders have been relatively upbeat about the course of the war since US President Donald Trump announced a new and more robust military strategy last year, with more air strikes and greater support for Afghan forces.
But the fighting in Farah underlines the continuing strength of the movement, which controls or contests almost half the country and has so far rejected peace overtures from Afghan President Ashraf Ghani.
In January, the Farah provincial governor resigned, blaming political interference and corruption. Residents of Farah city have complained bitterly about security in the province, where some police units are alleged to collude with Taliban fighters, selling them weapons and ammunition.
Although they have failed so far to take any major provincial cities, the insurgents have several times seized district centres, even if they have often been driven off soon after by government reinforcements.
With the approach of milder spring weather, security officials have said they expect to see fighting surge across the country as the Taliban step up pressure.
The US military's latest estimates from December show the Afghan government controls or has influence over 56% of districts, with insurgents controlling or contesting the rest. 
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