The blast at the Khan Research Laboratories (KRL) facility at Kahuta, near Islamabad, occurred when the technician was handling conventional explosives and there had been no damage to the nuclear facilities, said Army spokesman Shaukat Sultan.
AQ Khan, a controversial scientist known as the father of Pakistan's clandestine nuclear programme, passed away here on Sunday after a brief illness. He was 85.
It was prompted by the discovery that Pakistan may have been the source of crucial technology for Iran's secret nuclear programme.
Kochi Refineries shot up to the 20% upper deck on commencement of trading on Monday and stayed put at that level.