Investigators are looking for four men from the Democratic People's Republic of Korea who flew out of Malaysia the same day Kim Jong-nam, the DPRK top leader's half brother, apparently was poisoned at an airport in Kuala Lumpur, Malaysian police said Sunday.

Since Kim's death last week, authorities have been trying to piece together details of what happened. Malaysian police have arrested four people carrying IDs from the DPRK, Malaysia, Indonesia and Vietnam.

One of the suspects in custody, an Indonesian woman, told investigators that she was duped into thinking she was part of a comedy show prank.

On Sunday, Malaysia's deputy national police chief, Noor Rashid Ibrahim, said four more suspects were on the run. He said the men were from the DPRK and had flown out of the country on Feb 13, when Kim died.

"I am not going to disclose where they are," he told journalists, adding that Interpol was helping in the investigation.

Noor Rashid showed photographs of the four men, who were traveling on regular passports and are ages 33, 34, 55 and 57.

He also said there were three other people police wanted to question. It wasn't clear if they were suspects or simply wanted for questioning.

Kim Jong-nam, in his mid-40s, was waiting for his flight home to Macao when, officials say, he was set upon by two women.

He sought help at a customer service desk and said "two unidentified women had swabbed or had wiped his face with a liquid and that he felt dizzy", Noor Rashid said Sunday.

Kim died en route to a hospital after suffering a seizure, officials say.

Noor Rashid said Sunday that he expected autopsy results to be released within days. "We have to send a sample to the chemistry department, we have to send a sample for toxicology tests," he said.

Investigators also want to speak to Kim Jong-nam's next of kin to formally identify the body.

The case has raised tensions between Malaysia and the DPRK. Pyongyang demanded custody of Kim's body and strongly objected to an autopsy. The Malaysians went ahead, saying they were simply following procedure.

Kang Chol, the DPRK ambassador to Malaysia, said Malaysia may be "trying to conceal something" and that the autopsy was carried out "unilaterally and excluding our attendance".