The BBC is facing an angry reaction in Afghanistan after it changed the name of one of its local language Facebook pages to BBC Dari, one of the official names of the Afghan version of Persian or Farsi but one rejected by many local Persian speakers.
The Facebook page and other social media sites were bombarded by criticisms of the change. Many Persian speakers say the name Dari has been imposed historically by the traditionally dominant Pashto ethnic group, as an implicit denial of Afghanistan's place in the wider Persian-speaking world.
The reaction highlighted the sensitivity of linguistic and ethnic issues in Afghanistan, a country with a mix of over 35 languages spoken by ethnic groups including Pashtuns, Tajiks and Hazaras as well as Uzbeks and Turkmen.
It also echoed some of the tensions around the government led by President Ashraf Ghani, which was formed after the disputed 2014 election and which is seen by many Persian-speaking Tajiks and Hazaras as favouring his own Pashtun ethnicity.
While the Persian spoken in Afghanistan and neighbouring Iran has distinct accents and numerous variations in vocabulary and usage, other essentials are the same, with the gap between the two sometimes compared with the differences between the French spoken in France and Canada.
"My language is Farsi," said Mujib Rahman Rahimi, spokesman for Chief Executive Abdullah Abdullah, whose Jamiat-e-Islami party draws its support mainly from Tajiks.
"The time of betrayal of our language and culture is past. We will not allow anyone else to choose a name for our language," he wrote on his personal Facebook page.
However, not all reactions were negative and some other users supported the move, saying it reinforced Afghanistan's national identity: "I am from Afghanistan, not Persia or the Persian race," wrote one.
There was also no sign the reaction would harm the BBC's ability to report, or have major political repercussions in Afghanistan. Combined BBC services are estimated to reach about 6.6 million Afghans out of a total population of some 35 million, according to figures last year from the BBC Trust.
The head of the BBC's Afghan service, Meena Baktash, defended the use of the term Dari, noting that it was the official name of the language in Afghanistan.
She said the change was intended to link the Facebook page to the BBC Dari radio service, which was launched in 2003 and which, together with the BBC Pashto service, occupies an important place in the crowded local media landscape.
"There are absolutely no political and cultural reasons behind our decision," she wrote in a statement on Facebook, which, as in other countries, has taken off in Afghanistan to become one of the main sources of news and comment.
Along with Pashto, the language of the Pashtuns, Dari is named in the constitution as one of the two official languages of Afghanistan.
But many Afghan Persian speakers say their language is the same as the one spoken in Iran and Tajikistan and say the name Dari was favoured by past Pashtun leaders as a means of distancing Afghanistan from the Persian cultural sphere.
"The division of the Farsi language into Dari, Farsi and Tajiki is contrary to the reality of our common language and the vast expanse of our common culture and civilization," Abdul Hai Khurasani, a scholar and former aide to the late Mujahideen commander, Ahmad Shah Massoud, wrote in a letter which he posted on Facebook to the director general of the BBC World Service.