Police in Japan are searching the home of a man who threw an apparent pipe-bomb before a speech by Prime Minister Kishida Fumio.

Police are urging neighbors to stay away, as explosives were used in the incident on Saturday.

The police arrested 24-year-old Kimura Ryuji of Hyogo Prefecture on the spot on suspicion of forcible obstruction of business.

The suspect has reportedly said he will only submit to questioning when lawyers are present.

The prime minister was visiting a fishing port in Wakayama Prefecture to lend support to a candidate vying for a seat in an upcoming Lower House by-election. Just as he was about to begin speaking, a cylindrical object was thrown into the crowd.

Kishida was quickly escorted away from the site and was confirmed to be unharmed. Authorities say one police officer suffered minor injuries.

Meanwhile, an investigative source told NHK that one cylindrical object was connected with what is believed to be a wire.

Investigators say two such objects were found at the scene. One of them had exploded, while the other was in the possession of the suspect when he was subdued.

Investigators are analyzing the structure of the explosive devices, suspecting they could have been iron pipe bombs.