Al Jazeera has received reports that both army and police checkpoints have sprung up around Algiers, the country's capital, following the incident.

Kamel Mansari, a journalist based in Algiers, told Al Jazeera that the attacker - the chief commander of the police air division - had been dismissed by Tounsi a day earlier after weeks of disagreement.

Mansari said rumours had also been circulating in Algiers recently that Tounsi was about to be dismissed by the president.

"A lot of people are now questioning ... the real motivations of this assassination," he said.