Police are mobilising their intelligence and investigation resources to track down the criminals involved in a robbery as well as deliberately causing the death of a policeman yesterday.

Perak police chief Datuk Acryl Sani Abdullah Sani said police had classified the case as murder following the deliberate action of the criminals in ramming Lance Corporal Mohd Azuan Abdullah from the back while he was pursuing robbers who held up a cigarette van at the 10th Mile towards Alor Pongsu near Parit Buntar at 1.15 pm yesterday.

"This is an incident where the criminals wilfully rammed a member of the motorcycle patrol unit which we classified as murder," he told reporters after observing the proceeding of early voting for the Teluk Intan Parliamentary by-election at the Hilir Perak police headquarters multi-purpose hall here today.

In the early voting today, 410 out of the 60,349 registered voters comprised police personnel and their families.

Acryl Sani said based on initial information, the criminals had intended to kill Mohd Azuan.

In the incident, Mohd Azuan's colleague was also seriously injured.

He said police investigation would focus on the Toyota Wish which was found razed in a banana farm between Lunas and Ara Kuda in Tasek Gelugor, Penang.