"We're shocked and aggrieved at this tragic assassination," she said in parliament wrapping up a long discussion on the slain Awami League lawmaker, freedom fighter and trade unionist, gunned down by criminals on May 7.

Welcoming the boycotting Awami League MPs' return to parliament, the prime minister sought their cooperation in finding out the real killers and punish them by holding quick trial.

"We want your cooperation; let's give up accusation and counter-accusation, lets make joint effort to arrest those who killed him," Khaleda told the aggrieved opposition lawmakers.

The prime minister also requested the opposition to work together for the welfare of the nation, sinking individual interest. " We have fought war together, let's work together for the cause of the people and the nation."