KUALA LUMPUR, July 4 — The prime minister is concerned about the June 28 grenade attack at the Movida bar and has urged police to probe the incident linked to local Islamic State (IS) suspects, Inspector-General of Police Tan Sri Khalid Abu Bakar said today.

Khalid also urged the public to continue to work together with the police to hinder the activities of the terrorist group in Malaysia.

"We are very concerned about it of course, and the prime minister himself is very concerned about it and has given me very serious instructions to investigate this whole episode and to get everybody involved as soon as possible,” Khalid told reporters here.

Khalid today announced that police have nabbed two local male suspects that are believed to have been involved in the June 28 attack of the bar in a Puchong mall.

These two were nabbed on July 1 at the Port Klang area and are factory workers, he said.

He said police are still seeking two more male suspects for the same attack.

The two men sought over the attack are Md Saifuddin Muji and Jasanizam Rosni, with both their given addresses in Johor.

Khalid confirmed the Movida blast to be the first successful IS attack in Malaysia. He disagreed when asked if the police had slipped up after multiple successes in arresting suspected terrorists and foiling terror plots.

"They will find ways and means to avoid being detected and we will definitely try to be better,” he said.

Khalid said the police have beefed up security in public areas following the Movida blast that wounded eight people.

He said police arrested the two Movida attack suspects and 13 other local IS-linked suspects between June 28 and July 1 after receiving information from members of the public.

All 15 have been arrested under the Security Offences (Special Measures) Act, he said.

He added that more arrests can be expected in the future as part of the police operation against terrorism.