Police in Wakayama Prefecture on Thursday referred the suspect in an explosives attack against Prime Minister Fumio Kishida in April to public prosecutors on suspicion of attempted murder and other offenses.

The prefectural police apparently believe that the suspect, Ryuji Kimura, 24, intended to harm the prime minister and others, as an analysis of the explosive he used showed that it was highly lethal.

After the incident, fragments of the explosive were found in a container tens of meters from the scene.

On April 15, Kimura allegedly threw a pipe bomb toward Kishida, who was campaigning at Saikazaki port in the city of Wakayama, from about 10 meters away. It later exploded. Kishida was evacuated safely, but a police officer and a man in the audience were slightly injured.

Kimura was arrested at the scene on suspicion of forcible obstruction of business and was later served with a fresh arrest warrant on suspicion of violating the gunpowder control law.

A psychiatric evaluation began in late May to determine whether Kimura can take criminal responsibility. The examination will end on Friday and, based on the results, the Wakayama District Public Prosecutor's Office is expected to decide what action to take against the suspect.

According to police and other sources, Kimura is believed to have made two sets of explosives at his home in the city of Kawanishi, Hyogo Prefecture, between last November and April 15.