In a bitter taste of Pakistan's own medicine, the Sindhudesh Revolutionary Army, an internal freedom movement within Pak claimed responsibility for the attack. The blast took place near the main truck that was part of the rally in the Gulshan-i-Iqbal area, when two persons on a motorcycle lobbed a grenade, according to a Jamaat-i-Islami spokesperson. The rally was called off soon after the attack

KARACHI — More than 40 people were injured in a grenade attack on a rally in Karachi on Wednesday, as Pakistan marked the first anniversary of India's revocation of Kashmir's semi-autonomy.

The wounded were rushed to different hospitals, where one was in a critical condition, an official from the provincial health department said.

“A grenade was lobbed in the rally, causing several casualties,” Karachi police chief Ghulam Nabi Memon told Reuters.

The attack was claimed by Sindhudesh Revolutionary Army, a freedom movement outfit that has become active in the past months.

In June, four people were killed including two soldiers in three consecutive explosions claimed by the SRA.

The group wants Sindh province, of which Karachi is the capital, to break from the Pakistani federation. It has also announced its alliance with the Baluchistan Liberation Army, a militant group fighting for greater autonomy for the Baluchistan region in southwestern Pakistan.

The attack took place as similar rallies were held across the country. The Karachi rally, organised by Jamaat-e-Islami, a religious right party, was called off after the attack.

Last August, Prime Minister Narendra Modi's government stripped Jammu and Kashmir - India's only Muslim-majority state - of its special rights and split it into two federally administered territories.

The government said the change was necessary to develop the revolt-torn region and integrate it with the rest of India, but it infuriated many Kashmiris as well as neighbouring Pakistan.