Police are investigating those believed to have hacked the Twitter account of inspector-general of police Khalid Abu Bakar.

"I understand it was hacked using an overseas server. It is still under investigation," Bernama reported deputy inspector-general of police Noor Rashid Ibrahim as saying.

This morning Khalid's Twitter account was promoting Rayban sunglasses at a promotional price of US$24.99, without his consent.

On a separate matter, Noor Rashid said the police do not discount that the spate of shootings involves a small group of assassins.

"Yes, I cannot deny that some individuals are paid to assassinate others, and most of them are locals," he reportedly said.

He said police are still collating information to identify those involved in such activities.