Unidentified motorcyclists shot dead on Sunday disgruntled former secretary of Ayesha Gulalai in Lakki Marwat, Khyber Pakhtunkhwa, months after he filed a corruption reference against the Pakistan Tehreek-e-Insaf (PTI) MNA.Police say the assailants chased Noor Zaman's car before spraying it with bullets in Tajori area, leading to his death on the spot. The body was shifted to a nearby hospital. Zaman's family have yet to file a First Information Report (FIR) on the incident.Zaman's family has held four members of the Dawar Khel tribe - Umer Khan, Shaban, Syed Alam and Awal Khan - responsible for the murder. Police say they'll be arrested soon.On August 8, Noor Zaman, along with his aides, submitted an application against Gulalai, for embezzling millions of rupees in developmental schemes in her constituency.According to the reference, Gulalai and her father Shamsul Qayyum had been found involved in embezzlement and corruption in various provincial development schemes, saying it needed to be investigated on priority basis.Zaman had also threatened to present evidence before the provincial Ehtisab Commission and NAB if Gulalai did not apologise to PTI chief Imran Khan for levelling "baseless allegations" of sending her unsolicited text messages.Last week, Election Commission of Pakistan dismissed Imran's reference against Gulalai, seeking to de-seat her as member of the National Assembly.