Ibrahim Hazara, secretary of the Hazara Democratic Party (HDP), led a demonstration in the Balochistan capital Quetta and said some sequences in the film have maligned not only the community but also sullied Pakistan's image.
Threatening the film's director-cinematographer Kabir Khan, he said Quetta is "by no means a safe station" for him, The Daily Times said on Monday.
"The Hazaras are offended and hurt by the movie," he told the newspaper. "Not only does the movie make an effort to defame the Hazara community, it also creates a negative image of Pakistan."
"We want the movie director to apologise to the Hazaras of the world and urge the government of Pakistan to ban the movie and prevent it from being marketed in the country. The movie presents a negative image of Pakistan and Afghanistan," he added.
The HDP was joined by a large number of young Hazaras from the Hazara Students Federation (HSF).
A sequence in the film, starring John Abraham, Arshad Warsi and Pakistani actor Salman Shahid, shows the travelling team of journalists and filmmakers being stopped on a highway and being told by their guide that they could be waylaid and robbed by the local community of Hazaras.
The film is a socio-political comment on war ravaged Afghanistan and it portrays Hazaras as a ruthless and heartless community.
The Hazara community, which has an estimated population of around 200,000 and belongs to the Shia sect, say that derogatory language has been used against them in the movie.
Though Indian films are not screened in Pakistani halls, with the recent exceptions of "Mughal-e-Azam" and "Taj Mahal", there is a flourishing market of illegally imported films, CDs and DVDs, both in Pakistan and Afghanistan.
The movie, about an Indian journalist Sohail (John Abraham) who travels to war-torn Afghanistan to interview a captive member of the Taliban, has been dubbed in Hindi, Urdu and Darri, the report said.
The Afghan government had banned "Kabul Express" earlier this month. "The film has some sentences which were very offensive towards one of Afghanistan's ethnicities, namely the Hazara. For this reason it has been banned," Najib Manalai, Afghanistan's minister of culture adviser, was quoted as saying.
Hazaras make up about 10 percent of the Afghan population. They have supposedly descended from remnants of Genghis Khan's invading army.
Quetta is home to a large number of Hazaras who fled from the Afghan semi-autonomous province of Hazarajat in the late 19th century due to the excesses of the then Afghan king, Abdur Rahman.
"Kabul Express", based on Khan's personal experience in the country while making a documentary film, hit the screens last December and received critical acclaim.
While filming, Khan and both the actors received life threats from Afghan rebels. However, Khan shot the film on location under heavy security. He wrapped it up in 45 days. The Amitabh Bachchan starrer "Khuda Gawah" was based, although not shot, in Afghanistan during the 1980s and was said to be popular with both the supporters of the then Najibullah regime in Kabul and its opponents.