In a statement, Seberang Perai North police chief Asrie Shafie said the Mak Mandin police station received a phone call reporting the discovery of a suspicious package at a flat in Taman Pandan, Butterworth, suspected to contain explosive materials.

According to a witness, an explosion occurred at 12.56pm in front of a house there.

The police bomb disposal unit and the K9 team were dispatched to the scene and confirmed it was an improvised explosive device (IED) upon inspection.

The Seberang Perai North CID team subsequently arrested two men at two different locations in the Mak Mandin area near Butterworth.

Further questioning of the first suspect led to the discovery of another homemade bomb as well as the seizure of a homemade pistol, bullets and a karambit (curved knife).

One of the suspects admitted to learning how to make bombs from the internet and purchasing materials to make them online.

Both suspects tested negative for drugs and had no previous criminal convictions.

The case is being investigated under Section 6 of the Explosive Substances Act 1957; Section 8 of the Explosives, Firearms, and Dangerous Weapons Act 1958; and Section 8 of the Firearms Act 1960.

The motive behind the incident is still under investigation. The suspects have been remanded to assist in the probe.