KARACHI: At least three children were reportedly killed and several others injured in an explosion that took place in Karachi's SITE area on Monday, DawnNews reported.

The explosion took place near a seminary situated inside the Jamia Masjid Tahiri mosque in SITE's Frontier Colony area, rescue sources said, adding that the victims included children from the madrassah.

Hospital sources said many of the victims brought in were children aged between 8-12 years.

Rescue sources said the casualties were shifted to Abbasi Shaheed and Civil Hospital for medical treatment.

Police said the bomb was not hurled from outside but it may be in someones possession inside the seminary.

Earlier reports had said that the blast was carried out using a hand grenade.

Attacks in the provincial capital city have escalated ever since the Taliban announced their decision to not extend the ceasefire.

Police officer Shafiq Tanoli and three others were killed in an explosion that took place near Karachi's old wholesale vegetable market on April 24 whereas another blast in the city's Delhi Colony the next day had killed five others.