* At least 50 border police surrender to Taliban-officials
* Heavy casualties in fight for control of western Afghanistan
* Taliban says 90 border police had surrendered
At least 50 members of the Afghan security forces have surrendered to the Taliban in a fight for control of Afghanistan's western province of Badghis that has created heavy casualties, officials said.
Fighting in Afghanistan has intensified even as Taliban and US officials finished the latest round of peace talks on Tuesday, with both sides citing progress.
Afghanistan usually sees a marked increase in violence in spring.
Some 100 Afghan personnel who are part of the interior ministry's border police attempted to flee their posts into neighbouring Turkmenistan on Saturday, but they were prevented from entering that country, Badghis provincial council chairman Abdul Aziz Bik said on Sunday.
About 50 Afghan border police surrendered, while the remaining 50 continued fighting in the district of Bala Murghab, he said. Bala Murghab is the province's most populous district.
"These soldiers have been fighting against the Taliban for years and if they give up, they will be killed by Taliban," Bik said.
The district was at risk of falling to the Taliban unless Afghan forces receive air and ground reinforcements, Badghis provincial council member Abdullah Afzali said on Saturday.
Provincial councils are elected bodies that sometimes have closer connections to local residents than government officials have.
The Taliban said 90 border police had surrendered to the militant group. It posted photos on Twitter of a line-up of dozens of men who the Taliban said were captured border police, and it added that it had killed many others.
Jamshid Shahabi, a spokesman for Badghis' governor, said the Taliban had inflated its estimate of captured forces.
It was not clear how many total Afghan and Taliban forces have been killed or wounded in the battle for the district.
But the International Committee of the Red Cross tweeted that attacks in Bala Murghab had generated heavy casualties. The Red Cross said it had facilitated the handover of the bodies of 20 soldiers to the Afghan National Army Corps.
In a tweet, the Afghan ministry of defence said its forces had killed 12 insurgents in Bala Murghab, as part of operations across 10 provinces during the previous 24 hours. A spokesman for the ministry could not be reached for comment.
The Bala Murghab district has been a focal point of battle in recent months. The Taliban killed 20 Afghan soldiers and captured 20 less than a week ago.
The Taliban controls or contests nearly half of Afghanistan, the most since US-led forces ousted it from power in 2001, according to the US Special Inspector General for Afghanistan Reconstruction. The militant group conducts frequent attacks on Afghan security posts.
The Taliban, ousted in 2001, say they are fighting to expel foreign troops, topple the Western-backed Afghan government and restore its version of Islamic law.
Some 17,000 foreign troops are based in Afghanistan as part of a US-led NATO mission to train, assist and advise Afghan forces.