The incident took place near a seminary of Deobandi Sunni sect in Gulshan-e-, where the students had gathered for some refreshments.

"The unidentified gunmen on motorcycles specifically targeted the students of a nearby religious seminary and escaped after the shooting," Shahid Hayat, a senior police official told AFP.

"The initial investigations reveal that the killings were part of the ongoing wave of target killing in the city," he said referring to Karachi's sectarian, political and ethnic violence which have killed at least 1,100 people this year.

Another local police official Mohammad Hafeez told AFP that police were looking into why the students of this particular seminary were targeted.